The international turn in the study of the origins of late-19th-century imperialism: achievements,limits and new directions in the theory of uneven and combined development

Abstract

The late 19th century witnessed an unparalleled spasm of imperial expansion that redrew the world map into a handful of colonial empires. The first attempt to explain what caused this epoch was the Hobson-Lenin classical theory of imperialism. Nonetheless, over the past century, interwoven between other criticisms, many have problematised the theory’s ‘internalism’ – its negligence of the undeniable impact of interactive multi-societal co-existence (or, simply, the international) towards this outburst – and correspondingly rectified it. These critiques have constituted an international turn on the topic, which indeed seeks to incorporate the causal significance of the international. Yet, this turn faces two key limitations: an over-reliance on thick and supposedly atheoretical historical description and, on the flip side, a lack of historical specificity in theorising. To rectify these issues and further the international turn, this article argues that Leon Trotsky’s theory of uneven and combined development is a fruitful starting point.

Introduction

The late 19th century witnessed an unparalleled spasm of imperial expansion that redrew the world map into a handful of old-style, formal and territorial empires. A world of empires, rather than a world of nation-states, ¹ was among the main legacies of the long 19th century that would permanently change the trajectory of the international orders of the 20th and 21st centuries. ² Explanations of the origins of this spasm – that is, what caused not only pre-existing empires to ‘snap up the remaining independent territories’ of the world but also several new powers to participate in this ‘imperial carnival’ – have been among the main inquiries of those studying what historian Eric Hobsbawm famously popularised as the ‘age of empire’. ³

The Hobson-Lenin thesis was arguably the first attempt to explicitly theorise the origins of late-19th-century imperialism. ⁴ It argues that during the late 19th century, mature/monopolistic capitalism faced a crisis of falling profits in advanced capitalist countries, which motivated overseas capital investments in foreign territories. The bourgeois forces who controlled these investments, in turn, influenced their governments to politically and militarily control where these investments were.

Much has been written about the various shortcomings of the Hobson-Lenin explanation of late-19th-century imperialism, so much so that historian Oron Hale rightly declared in 1971 that ‘the Hobsonian foundation has been almost completely demolished’. ⁵ Interwoven between these criticisms, nonetheless, is the issue of ‘internalism’. Internalism is the tendency to conceptualise societal processes and outcomes as isolated within a society, which ignores the consequences of interactive multi-societal co-existence (or, simply, the international). ⁶ It can indeed be observed in the Hobson-Lenin thesis: in blaming the investment-outlet-seeking middle class as the singular culprit, the theory artificially isolates the processes that led to late-19th-century imperialism as taking place strictly within a society.

Against this weakness of the original theory, there has been an international turn in the study of the origins of late-19th-century imperialism. Here, scholars have highlighted important international dynamics that played more important roles in inducing this ‘age of empire’ compared to the workings of capitalism within any of these empires. This turn has been protracted – the earliest piece identified below was written in 1934 – and transdisciplinary – writers contributing to this awareness of the causal significance of the international in explaining late-19th-century imperialism have come from a diversity of disciplines and fields across the humanities and social sciences.

Yet, despite the turn’s abundant achievements, this article argues that there is still space for theoretical innovations that can further our understanding of the origins of the ‘age of empire’. Specifically, I propose to adapt a recent addition to the pool of international social theories ⁷ in IR – the revival of Leon Trotsky’s theory of uneven and combined development (UCD) – to rectify two existing limits of the international turn. Those limits are, on the one hand, an over-reliance on thick and supposedly atheoretical historical descriptions and, on the other hand, a lack of historical specificity in theorising.

This article proceeds in four steps. First, I review the Hobson-Lenin thesis and show that indeed internalism is one of its main shortfalls. Second, I engage with the aforementioned international turn – the abundance of anti-internalist attempts to re-write and/or re-theorise the origins of late-19th-century imperialism – which has demonstrated that indeed one must incorporate the causal significance of the international to better account for the origins of the ‘age of empire’. Third, I argue that despite the turn’s already plentiful contributions, it has not yet reached its full explanatory power, limited by the aforementioned issues of over-reliance on thick historical descriptions and ahistoricist theorising. Finally, I adapt UCD into a meso-theory of the origins of late-19th-century imperialism to rectify both of those issues. Importantly, as the explicit application of UCD into explaining late-19th-century imperialism diverges from the typical uses of the theory thus far, the article also critically re-engages with and innovates the theory’s existing concepts, namely backwardness and combination.

The Hobson-Lenin thesis and its internalism

Imperialism, defined as the subjugation of other peoples and territories under one’s rule, has existed in various forms throughout human history. ⁸ However, the late 19th century saw an unprecedented outburst of imperial activities that united the globe under one closely interconnected yet starkly hierarchical system. Imperial powers old and new took over previously independent areas in Africa, Asia and the Pacific Islands, leaving almost nothing by the end of the First World War.

As mentioned, the first attempt to theorise the origins of this important epoch is arguably that by John A. Hobson and Vladimir Lenin, who argue that imperialism – the rampant political seizures of this period – was driven by the need to find new markets and investment opportunities for surplus capital, which cannot be absorbed domestically due to economic inequalities and overproduction inherent in capitalist economies. ⁹ There are, of course, important differences between Hobson and Lenin as summarised by Arthur Eckstein:

Lenin emphasized the economics of monopoly as a driving force behind imperial expansion; Hobson has much less to say about this. Hobson tended to equate expansion with outright annexation, whereas Lenin’s definition of empire was more elastic, and included the concept of ‘informal control’. In Lenin, Hobson’s vague groups of mysterious financiers motivated by the economics of ‘over-saving of capital’ are replaced by banks as the specific institutional force behind expansion. And whereas Hobson believed that the crisis he perceived within capitalism (and especially British capitalism) could be reversed by reform, Lenin believed the process was one of irreversible world-wide development, leading to inevitable revolution. ¹⁰

Nevertheless, as Eckstein also concludes, the enduring coupling of the two into a single Hobson-Lenin thesis rests on a fundamental shared core that Lenin adopts wholesale from Hobson’s Imperialism: the primacy of overseas investments as the engine behind post-1870s global imperial expansion. ¹¹

Despite its seemingly compelling logical sequence that also shows a sharp instinct for historical specificity by incorporating the role of capitalism, the thesis’s many flaws have been thoroughly revealed by subsequent scholarship. From outside but also from within the Marxist tradition, critics have problematised its theoretical oversimplification of states as mere agents of economic forces, ¹² its negligence of the role of the pre-capitalist ruling classes during the late 19th century, ¹³ its empirically weak claim that capital exports only happen after market over-saturation, ¹⁴ and, most detrimentally, its failure to satisfactorily explain the very object that it claims to – the origins of many important empires during this period such as those of Britain, France, Germany and Japan. ¹⁵ As a result, alongside Hale’s declaration of the thesis’s ‘demolished’ foundation mentioned in the introduction, Giovanni Arrighi laments from within the Marxist tradition: ‘by the end of the 60s, what had once been the pride of Marxism – the theory of imperialism – had become a tower of Babel, in which not even Marxists knew any longer how to find their way’. ¹⁶

Interwoven in these critiques of the thesis, I argue, is one issue that IR is uniquely positioned to engage with: internalism. But what is internalist about this explanation of late-19th-century imperialism? Is it not true that by emphasising overseas investments, Hobson and Lenin show an awareness of relations beyond borders?

I argue that inter-societal interactions before the rise of late-19th-century empires play no role in Hobson’s and Lenin’s explanation. In their account, they use the rise of the investment-outlet-seeking bourgeoisie – understood as the outcome of the uni-linear evolution of capitalism – to singularly explain late-19th-century imperialism. In arguing so, the societal processes that led to imperial pursuits – the formation of bourgeois interests in overseas investments and the state’s interests in protecting them through political control – are assumed to be taking place strictly within a society. This is what internalism means: nowhere in this explanation of the origins of late-19th-century empires is the significance of multi-societal co-existence incorporated. ¹⁷

Yet, so what that amidst inter-related issues, internalism is yet another shortfall of the Hobson-Lenin explanation of late-19th-century imperialism? Theories are simplifications, which always leave out certain aspects of reality. Could it be possible that in the case of the origins of the ‘age of empire’, dynamics beyond each imperial metropole’s border were simply absent or causally insignificant enough to be ignored? No: as the anti-internalist works reviewed in the following section show, Hobson’s and Lenin’s choice not to incorporate the international is at the core of their thesis’s many mentioned failures, and by bringing in the international, much more about the origins of late-19th-century imperialism can be comprehended.

Achievements: the international turn in the study of the origins of late-19th-century imperialism

Since the publication of the now-discredited Hobson-Lenin thesis, there has been a flourishing of anti-internalist writings on late-19th-century imperialism, collectively constituting an international turn in our understanding of this topic. These writings have not been curtailed within a single specialised discipline: one instead encounters them in, for example, history, global history, area studies, postcolonial scholarship, and, of course, IR. This section provides an overview of some of the most notable of these works, which are presented under two categories: writings without explicit theorisation of the international, which lean towards descriptive aims, and writings with explicit theorisation of the international, which lean towards explanatory aims. This is a simplistic and imperfect way to categorise them – among historians with descriptive goals, for example, some are shown below to have attempted to formulate an explicit causal theory for the impact of the international towards the origins of late-19th-century imperialism. As such, this categorising strategy should only be understood as a useful shorthand, which aims to open and not close further investigation.

The main goal of this overview is to show that understandings of late-19th-century imperialism have advanced significantly over the past century, doing so through, among other contributions, a growing scholarly sensitivity to the causal significance of the international. The Hobson-Lenin narrow focus on each imperial metropole has indeed been thoroughly problematised; thus, any re-engagement with the topic, like that of this article, must carry forward the many important insights proffered by this scholarship.

Descriptive accounts of the origins of late-19th-century imperialism

Indeed, many have put forward compelling descriptive accounts that recognise the role that the international had in the origins of late-19th-century imperialism.

Among the earliest of them is Gallagher & Robinson’s famous 1953 article, which popularised the term ‘the imperialism of free trade’ to describe British imperial strategies for most of the 19th century. ¹⁸ These two writers use the case of British activities in Latin America throughout the 19th century to demonstrate that imperialism had already been in existence during the free trade period of capitalism. They argue that the mid-Victorians were as prepared to resort to colonial means as the late-Victorians, but the former could often achieve their goals of maintaining British paramountcy without the need for doing so – ‘the usual summing up of the policy of the free trade empire as “trade not rule” should read “trade with informal control if possible; trade with rule when necessary”’. ¹⁹ As such, Gallagher & Robinson imply that the explosion of formal empires since the 1870s was not due to the evolution of capitalism into a monopolistic, more imperialistic stage as Hobson and Lenin suggest.

Instead, to explain the fact that ‘the late-Victorians . . . were driven to annex more often’, they draw attention to the intensification of ‘foreign challenge’ during the late 19th century. ²⁰ Through examples such as the British fear of the French taking advantage of the chaos in Egypt leading up to 1882 to insert themselves into the British trade route to India, Gallagher & Robinson offer an internationally sensitive account for why old-style imperialism became more popular in the late 19th century. ²¹

Another popular critique of the Hobson-Lenin thesis during this time was Fieldhouse’s 1961 article, which provides one of the most thorough expositions of the thesis’s empirical weaknesses. ²² Fieldhouse, drawing from earlier statistical studies, ²³ demonstrates that while British investments did go overseas, they avoided Asian and African tropical regions – which witnessed the growth of formal empires between 1870 and 1900 – and instead went to other European states, Latin America or the United States. ²⁴ As such, he further consolidates the claims made by Gallagher & Robinson that the most valuable parts of empires had already been achieved by the 1870s. ²⁵ Fieldhouse also observes that German imperialism occurred two decades before the age of German cartels, ²⁶ and that the financially formidable United States was the least imperialist out of all the advanced capitalist states during this period. ²⁷

After detailing the empirical shortfalls of the Hobson-Lenin thesis, Fieldhouse re-imagines how to study the origins of late-19th-century empires by hinting at indeed the international: ‘the outstanding feature of the new situation was . . . the preoccupation with national security, military power and prestige’. ²⁸ He argues that Europe was drawn into a competition through which colony acquisitions were the means. ²⁹ For him, no example is more compelling than that of Germany: ‘Bismarck in particular recognized that . . . Africa and the Pacific had little to offer Germany, whatever national advantages those with private interests there might claim. At best they might offer naval bases, a strictly limited trade, and bargaining counters for use in diplomacy’. ³⁰ Germany, confronted by the more economically advanced, sought to resolve its precarious situation by acquiring colonies – ‘colonies thus became a means out of the impasse; sources of diplomatic strength, prestige-giving accessions of territory, hope for future economic development’. ³¹ And it is not just the late-comers that are featured here: ‘it was the threat of German or French occupation of the key to the Nile and Egypt that decided [Salisbury and Rosebery] to act’. ³² All these remain very compelling stories of what drove the Europeans to seek formal colonies during the period.

This early international turn in the studies of European empires also had its counterpart in the works of scholars writing about the origins of the only major non-European empire during this period: Japan. Yet perhaps because Japanese imperialism started amidst overwhelming European imperial activities in East Asia, an international turn took place much earlier.

As early as 1934, stemming interestingly from Marxists studying the case of Japan, Tanin & Yohan argue that post-1894 Japanese imperialism stemmed from the ruling samurai, instead of capitalists, who sought to resist ‘white imperialism’. ³³ They emphasise that even when Japanese imperialism became more capitalistic in its motivation after 1905, it was not the capitalists alone but instead an allegiance between them and the ruling class, who kept Western imperialism firmly in its thinking, that propelled expansion. Similarly, Shoichi Fujii, a Japanese Marxist, observes that pre-First World War Japanese imperialism was ‘dependent upon and subordinate to the imperialism of other powers’, stressing that the Japanese government was driven by a perceived need to conform with ‘a world structure dominated by capitalism and imperialism’. ³⁴ As the most influential Marxist writer on this subject, Kiyoshi Inoue qualifies that Japan was not simply resisting Western imperialism but also cooperating with it in certain aspects to augment capitalism at home. ³⁵ He then provides an excellent analysis of the tripartite relationship between the Japanese military bureaucracy, the Japanese capitalists, and an array of Anglo-American officers in the region. As Beasley assesses these works from the Marxist tradition, these writers became very quickly aware that the Hobson-Lenin causal sequence was quite far off from the reality of Japanese imperialism and chose to modify it by not only taking serious Schumpeter’s insights about the critical roles of the heirs of the feudal class, but also incorporating the influence of external influences. ³⁶ Beasley very cogently puts his observation of the overall argument of this literature: ‘Japanese imperialism becomes the illegitimate child of Western capitalism, with international rivalry as midwife’. ³⁷

This sensitivity of the international has been carried forward beyond the Marxist tradition in writings on the origins of the Japanese empire. For example, Marius Jansen shines more light on the ideological dimension of imperial motivations – ‘most articulate Japanese were prepared to accept the argument that Darwinian selection and competition in the international order made imperialist expansion the expected path’ – showing that both within the government as well as the intelligentsia, the justifications for colonising Japan’s neighbours were very quickly internalised. ³⁸ One must also note Akira Iriye’s impressive body of works, which provides a survey of the Japanese changing responses to the Western example throughout the late 19th and early 20th centuries. ³⁹ For the opening years of Japanese imperialism, Iriye mainly reiterates the above Marxist explanation: Japan was balancing economic and military means to respond to Western imperial activities in the region. Indeed, glimpses or even full visions of the significance of the international towards the origins of Japanese imperialism are not rare in this scholarship.

Lastly among these works that are categorised as constituting a descriptive international turn in studying the origins of late-19th-century imperialism, writings in global history since the beginning of the 21st century have continued to uphold anti-internalist commitments. Most influential among them is Christopher Bayly’s volume on the long 19th century where he, through the medium of nationalism, connects the international with European imperial activities – ‘nationalism and conflict in Europe made states more aware of their competitors abroad and more inclined to stake out claims and prefer their own citizens’. ⁴⁰ Just like others before, he explicitly rejects the Hobson-Lenin blame on capitalists and instead looks at the tension among states during this period – ‘the grand orchestrators of the new imperialism were not international capitalists, as Lenin averred, but national governments which encouraged the commercial interests of their own citizens to pre-empt rival mining, telegraph, railway, or commodity companies’. ⁴¹ After making these general observations, the story he tells of the origins of late-19th-century imperialism is indeed one that highlights international connections. ⁴²

Explanatory accounts of the origins of late-19th-century imperialism

So far, I have overviewed some notable accounts that have explicit descriptive aims towards the internationally entangled origins of late-19th-century imperialism. They have been categorised as ‘descriptive’ because while they do pay attention to the international, it is little theorised, at least not as carefully theorised as the domestic socio-political processes that these accounts also capture. Nonetheless, as mentioned, there have also been explanatory accounts that explicitly theorise the significance of the international towards the origins of the empires during this period.

A recent contribution from global historian Jeremy Adelman is firmly located in this category. Adelman starts with a very similar observation about the lack of theorisation of the significance of the international – ‘empires are seldom conceptualised as pieces of a larger puzzle shaped by other pieces, other empires’. ⁴³ He then looks to ‘approaches that entangle or cross polities’ from international political economists, global historians and indeed IR scholars, synthesising them into what he calls a theory of ‘mimesis and rivalry’ between empires. ⁴⁴ In simple terms, he argues that ‘competition and copying’ were not only the results of imperial expansion but also what spurred it in the first place. ⁴⁵ The remainder of his article carries on to show how these two dynamics were underlining the expansion of empire(s) since especially 1492 with the European encounter of the Americas. One in fact sees an allusion to these two dynamics in the above work of Bayly as well, albeit less developed – ‘contending territorial empires took on sharper lineaments and became more antagonistic to each other at the very same time as the similarities, connections, and linkages between them proliferated’ ⁴⁶ – which Adelman himself recognises. ⁴⁷ Nonetheless, the latter qualifies that while Bayly suggests that these dynamics were curtailed to the long 19th century, Adelman maintains that they had much deeper taproots even if they might have been intensified post-1830s. ⁴⁸ As such, to reiterate, Adelman’s theory claims to capture the intensification of mimesis and rivalry among empires since the end of the 15th century, including late-19th-century imperialism.

Nonetheless, as expected, when it comes to theorising the significance of the international towards the origins of late-19th-century imperialism, IR is, or should be, the go-to discipline to look for relevant attempts. Indeed, regarding this particular subject, there have been two notable theoretical engagements.

First is Kenneth Waltz’s engagement with the Hobson-Lenin thesis in Theory of International Politics. Just like all writers mentioned thus far, Waltz uses the Hobson-Lenin thesis as an example, in fact the example, of an internalist (or reductionist) theory. ⁴⁹ While he explicitly claims that he is ‘not arguing that capitalism had nothing to do with British and French imperialism’, ⁵⁰ he argues that it is not capitalism per se but instead the international imbalances in capabilities favouring advanced capitalist countries that produced late-19th-century imperialism. ⁵¹ As such, for Waltz, it is not the intricate economic workings of the capitalist mode of production itself but instead the resultant international disequilibrium of power that should be the starting point to understand the origins of late-19th-century imperialism or, importantly for Waltz’s argument, any form of imperialism – ‘in its heyday mercantilism was the cause of imperialism in just the same spurious sense that capitalism was later’. ⁵² In other words, as imperialism has been practised by any society that holds uneven advantages compared to others, the nature of such societies is ‘unimportant’ – imperialism is expected when there are great powers in the system. ⁵³ He is in fact not alone in his insistence that good-old geopolitics and not capitalism per se was the main culprit: as Alex Callinicos observes, prominent sociologists like Anthony Giddens, Michael Mann and Theda Skockpol have also, like Waltz, reproached Marxists for failing to see that geopolitical competition had been a transhistorical phenomenon governed by a logic irreducible to that of class exploitation. ⁵⁴

Second is Suzuki’s critical application of the English School to the case of the emergence of Japanese imperialism. He argues that Japan was not only well aware of the ‘dark’ imperial side of the European international society, but it also mimicked such practices to demonstrate to the West that it was ‘civilised’ and thus should be a member of ‘society’. ⁵⁵ Suzuki rightly problematises how the classical ES account whitewashes imperialism by representing it as simply Europe carrying the ‘white man’s burden’ by bringing civilised institutions to the non-West and argues that such a narrative fails to capture the brutality of imperialism. Put differently, by depicting ‘expansion’ as a well-intentioned Europe teaching the non-West a reasonable structure of civilised and modern institutions, earlier ES works fail to capture the consequences of the ‘dark’ side of coercive imperial practices. One of these consequences, as portrayed by Suzuki, was Japanese imperialism. Through understanding the ‘dark’ reality of the Japanese encounter with Europe, he argues that one of the main goals of Japanese imperial activities in East Asia, if not the main goal, was to help Japan to be recognised as a full member of the existing European international society, where the fact that Japan practised imperialism was consistent with its understanding of such a society. ⁵⁶ His central argument is summed up neatly at the opening of the book:

[A]s Japan increasingly associated itself with the Society, it began to emulate the Society’s “civilized” members by engaging in imperialist policies designed to demonstrate that it had attained a level of (European) “civilization” high enough for it to qualify to play a part in its forcible dissemination in Asia. ⁵⁷

In this account, Japan simply abided by the rules of the imperial ‘game’ to be recognised as a ‘player’. It was situated within an international environment where the West had had centuries of imperial expansion, a context which could be reasonably argued to have facilitated Japanese ambition towards imperialism, in doing so demonstrating to the West that it is ‘civilised’. Further, in adopting imperialism, Japan ensured its gains, whether they be material or status/recognition, by adhering to the Western framework. As he rightly assesses it himself, this is ‘an international explanation for Japanese imperialism in the late nineteenth century’. ⁵⁸

While aiming to explain a particular empire, theoretically, Suzuki’s explanation is consistent with the model of copying and competition highlighted by Adelman above, albeit with a particular emphasis on the copying side. This mimesis-centric explanation to capture the derivative relationship between empires has also been famously highlighted by Homi Bhabha and recently reiterated by Robert Eskildsen again for the case of Japan. ⁵⁹

As seen in these reviewed works, the international turn is at the front and centre of studies on the origins of late-19th-century imperialism. The highlighted writers, among many others, have thoroughly shown why internalism is a serious and substantive issue in this particular topic, and correspondingly turn their attention to the international, empirically and theoretically. Theories necessarily contain omissions, but the omission of the international, starting with the Hobson-Lenin thesis, has been shown by this turn to be a catastrophic misstep in accounting for the ‘age of empire’.

Limits: thick historical descriptions and ahistoricist theorising

Despite the above achievements, I argue that this international turn has not yet reached its full potential. Specifically, it is constrained by two limits: on the descriptive side of scholarship, an over-reliance on thick and supposedly atheoretical historical descriptions, and on the explanatory side of scholarship, a lack of historical specificity in theorising.

Against simplistic theories like the Hobson-Lenin thesis, even if they have been discredited, extensive historical writings and descriptions that do not advance an alternative theory would be, perhaps unjustly but understandably, relegated to being secondary empirical modifications that reflect the complexity of what is actually ‘out there’, which theorists themselves are already aware of. Without explicit theorisation, thick descriptions are at best treated as untheorisable historical contingency. In other words, as illuminating as the accounts of how international processes fed into the rise of late-19th-century imperialism put forward especially by the more descriptive side of the international turn above, their lack of theorisation prevents them from fully realising the explanatory potentials of the international turn.

Gallagher and Robinson’s work, for instance, vividly describes how British imperial policy flexibly shifted between informal control and direct rule, depending on what best served British interests in specific international contexts. ⁶⁰ However, their account lacks an overarching theoretical framework to explain why and how these strategic shifts occurred. Their case-specific insights, while compelling, remain loosely connected and limited in their capacity to provide a causal explanation that elucidates broader patterns across the imperial landscape of this epoch.

Fieldhouse’s writings provide another example: while he effectively counters the Hobson-Lenin thesis with empirical evidence that British investments often bypassed the tropical colonies targeted by formal imperialism, his approach remains limited by its focus on dismantling specific claims rather than developing an alternative theory. ⁶¹ Fieldhouse highlights security and national prestige over economic motives, particularly through Germany’s colonisation efforts, which he sees as aimed at securing diplomatic leverage. However, without a coherent theoretical foundation, these observations do not add up to a structured causal account of how such motives interplayed with economic conditions or evolved from a broader geopolitical context. Thus, while Fieldhouse’s insights challenge the reductionist tendencies of the Hobson-Lenin thesis, they remain empirical observations that, without theoretical cohesion, risk being treated as isolated contingencies rather than as elements of a broader explanatory model.

This same pattern appears in the descriptive international scholarship on Japanese imperialism, for example in the work of Tanin and Yohan, who highlight the ruling samurai class’s efforts to resist ‘white imperialism’. ⁶² Their account emphasises Japan’s reaction to Western expansion, yet it remains confined to historical detail without a unifying causal framework that might explain why these imperial tendencies arose in specific forms in Japan. Without theorising the interrelation between Japan’s internal political dynamics and the larger international pressures it faced, these accounts remain historical vignettes.

But what about the attempts within the international turn that do theorise? I argue that while their theorisations of the significance of the international is indeed in the right direction, among them, there has yet been a theory that, like the Hobson-Lenin thesis, pays attention to historical specificity by attempting to theorise the importance of capitalism, even if the latter’s theorisation of the role of capitalism in relation to late-19th-century imperialism is indeed flawed. Put differently, these theories often prioritise abstract international dynamics, treating imperialism as a transhistorical phenomenon rather than one deeply rooted in the particular configurations of the late-19th century. Although they incorporate aspects of the international into their explanations, these accounts fall short of providing a historically grounded analysis that fully engages with the specific characteristics of this period.

Adelman’s work, for instance, proposes a theory of ‘mimesis and rivalry’ to explain how empires engage in cycles of competition and imitation. ⁶³ While compelling in its breadth, this theory is structured to capture imperial dynamics across different eras and is not tailored to the unique conditions of the late-19th century, particularly the transformative effects of capitalism. Adelman’s framework suggests that imperialism results from a universal impulse to emulate successful rivals and secure a competitive edge. Yet, by framing competition and copying as constants across time, Adelman risks flattening the distinct economic and political pressures that characterised the late 19th century. His transhistorical lens implies that empires act in similar ways regardless of context, missing the specific motivations associated with the capitalist dynamics of this period. As a result, his work lacks a causal framework that fully explains why the late-19th century, in particular, witnessed an unprecedented surge in territorial expansion.

Waltz’s approach similarly abstracts imperialism into a transhistorical result of power imbalances, suggesting that imperialism is an inevitable outcome whenever one state gains a significant advantage over others. ⁶⁴ By treating imperialism as a byproduct of uneven power distributions, Waltz’s theory overlooks how the unique configurations of late-19th-century capitalism reshaped the motivations and mechanisms of imperial expansion. This ‘unbalance of power’ framework fails to account for the specific pressures that capitalist development exerted on the relevant actors of this period. In Waltz’s model, imperialism becomes a timeless response to geopolitical inequality rather than a phenomenon shaped by the historical dynamics of the time.

Finally, Suzuki’s work on Japanese imperialism offers another instructive example. ⁶⁵ His analysis highlights Japan’s emulation of Western imperial powers as a means of gaining recognition and legitimacy in an international society dominated by European standards. However, Suzuki’s focus on Japan’s desire for status and acceptance, while insightful, does not delve into the specific economic and political factors that made imperialism an attractive path for Japan at this historical juncture. By emphasising Japan’s imitation of Western norms as a universal strategy for state advancement, Suzuki’s account underplays how Japan’s imperial ambitions were shaped under a particular period of global transformation. His framework thus falls short of explaining why Japan’s response to international pressures took the specific form of territorial imperialism, rather than other forms of participation or resistance in the global order.

Adelman’s, Waltz’s, and Suzuki’s respective theories that deal with the causal significance of the international can, I agree, be theories of how international relations could give rise to imperialism trans-historically. In fact, Adelman and Waltz are explicit about this aim. ⁶⁶ Indeed, both Waltz’s argument that an unbalance of power expectedly leads to imperialism and Adelman’s and Suzuki’s emphasis on how empires compete with and copy from each other do say something about the origins of all imperialisms broadly and late-19th-century imperialism specifically. However, as argued in each case above, the epoch-making impact of capitalism must play an integral role in the story rather than being treated as epiphenomenal at worst and a historical contingency at best.

New directions: the theory of uneven and combined development as a theory of the origins of late-19th-century imperialism

A contribution that would innovate this international turn in the study of late-19th-century imperialism, thus, is a theory that, first and foremost, is an actual theory as opposed to thick descriptions, containing an explicit causal sequence to explain the origins of the ‘age of empire’. Within that causal sequence, it must incorporate both the causal significance of the international, which has been shown by the above international turn to be highly relevant towards the rise of late-19th-century imperialism, and the significance of capitalism, which is required to maintain a high degree of historical specificity. In other words, this new theory for late-19th-century imperialism is expected to carry forward the Hobson-Lenin correct intuition about the impact of capitalism during this period (though not their actual execution of such an intuition) as well as its commitment to parsimony and theoretical coherence, doing so while incorporating the significance of the international. As daunting as this task may sound, there is already a source for such a theory from recent developments in IR: the revival of Leon Trotsky’s theory of uneven and combined development.

This selection of UCD to fulfil the task of innovating the international turn in the study of the origins of late-19th-century imperialism, I argue, builds upon the calls by important contemporary Marxists who have written extensively on the relationship between capitalism, the international and imperialism. Prominent examples include David Harvey – who argues that the international and capitalism are two sides of a dialectic that are simultaneously in motion and irreducible to each other ⁶⁷ – and Callinicos – who proposes a kind of explanatory pluralism where capitalist imperialism, including its late-19th-century variant, is best understood as the intersection of economic and geopolitical competition. ⁶⁸ UCD, as explicated below, is arguably a theoretically coherent expression of these broad pointers, and as such is the sought-after innovation for the above international turn. ⁶⁹

The revival of UCD is about to finish its third decade in IR. ⁷⁰ Thus, instead of providing a complete explication of the theory, which is abundantly available elsewhere, ⁷¹ I will focus more on how its concepts are operationalised in explaining the origins of late-19th-century imperialism, qualifying potentially novel interpretations of the theory when necessary. Just like how the classical Hobson-Lenin theory of imperialism is a meso-theory (intermediate-level theory) of Marxism, one can understand the below exercise as an attempt to construct a meso-theory for late-19th-century imperialism based on the more general theory of UCD. ⁷²

Unevenness

UCD starts with what Trotsky observes as the ‘most general law’ of human history: unevenness – the world has comprised a variety of societies of different sizes, cultural forms and levels of material development. ⁷³ The term aims to capture both the quantitative and qualitative features of world politics, respectively the co-existence of not a single but multiple societies and their diverse characters. ⁷⁴ Subsequently and importantly, any application of UCD historicises this unevenness, asking what the configuration of unevenness of the context in question is. ⁷⁵ It is through this context-begging and not generalisability-seeking mode of theorising that UCD easily allows for the entry of one important aspect of capitalism when the theory is applied to the context of the late 19th century.

Specifically, during this period, capitalism, alongside its societal impact in disrupting modes of production and social structures, also reconfigured international unevenness. The emergence of capitalism opened up an enormous competitive gulf between societies. ⁷⁶ On the one hand, the very familiar story in recent postcolonial and international historical sociological scholarship appears: capitalist development culminating in Western Europe and the United States allowed them the economic capabilities well beyond others, shaping an overarching and unprecedented macro-unevenness between the West and the East. ⁷⁷ While Asian societies – especially those of China and India – were previously respected in many parts of Europe where Europeans interacted with Asians as equals or even as supplicants, ⁷⁸ the scale tipped. Over the course of the century, China’s share of global production dropped from 33% to 6%, India’s 20% to 2% and today’s ‘Third World’ from 75% to 7%. ⁷⁹

On the other hand, zooming further into the West, stark unevenness induced by capitalism was present as well. Britain, the first reaper of modern capitalism, was by all means ahead of all other great powers in continental Europe and the United States for most of the 19th century. ⁸⁰ Up until the last decades of the century, the British dominated world trade and controlled, among others, the immensely profitable Indian colony. ⁸¹ Compare this to, for example, the recently consolidated Germany and Italy and the new United States established by the revolutionary colonists, there were clear vectors of unevenness between Western powers as well.

Heightened unevenness as an, if not the, important and consequential effect of the international towards late-19th-century imperialism has, in fact, been hinted at by many of the discussed scholars. Waltz’s ‘unbalance of power’ as the ground for imperialism comes right to mind. Furthermore, in the opening pages of Bayly’s volume, for example, he states that ‘[n]o world history of [the long nineteenth century] could possibly sidestep the central importance of the growing economic dominance of western Europe and North America’. ⁸² Adelman, too, makes allusions to heightened unevenness, which he calls ‘global disequilibrium’, as an important causal locus of the formalisation of empires: ‘an emerging territorial consciousness heightened the global disequilibrium, made it more intractable, and increasingly externalised it to fringes of states systems where once customary patterns of tribute and vassalage prevailed’. ⁸³

Thus, right from its opening concept – unevenness – this UCD-based theory of imperialism already manages to incorporate the significance of both the international and capitalism during the late 19th century. As others have also hinted at, this observation of heightened international unevenness is a more fruitful starting point to understand the sources of the ‘age of empire’ rather than any single-society process.

Backwardness

But simply pointing at the capitalism-induced unevenness of the late 19th century and arguing that it was an important cause of the imperialism of this period is not satisfactory. If this is where theorising stops, then this theory of late-19th-century imperialism contributes little more than the mentioned others who have also pointed to this truism, including and especially Waltz. Even if stark unevenness indeed made imperialism a likely outcome in the late 19th century, explaining imperial foreign policies still requires an analysis of the societal consequences of this unevenness and how they were connected to imperialism. Put differently, further theorising is needed to connect the observation of unevenness to the actual emergence of imperial ambitions and policies within each imperial metropole during this period. ⁸⁴ Waltz explicitly gives up on the possibility of such a unified theory that captures both systems-level and unit-level causes while retaining elegance, preferring to leave them separate. ⁸⁵ Can UCD offer it?

Yes, but I argue with some further explorations of its concepts. Carrying on the UCD’s theoretical sequence, the theory states that once a society becomes aware of unevenness – what Trotsky famously captures through his phrase ‘the whip of external necessity’ (hereafter, the whip) ⁸⁶ – it devises strategies to ‘catch up’. However, from just identifying the ‘whip’ and arguing that ‘catching up’ will happen, one cannot fully account for why certain types of reactions take place. Strategies for catching up are rarely obvious, leaving ample space for (mis-)interpretations – in attempting to catch up, societies have augmented transformations as wide-ranging as top-down capitalist industrialisation to re-imagining how to write novels. ⁸⁷ Typical applications of UCD gloss over this problématique – why certain strategies are favoured and not others – by simply recording post-whip ‘combined’ changes in society.

While there is nothing wrong per se with such a theoretical choice of simply recording the combined changes that a society augments to ‘catch up’, I argue that there is a way to generalise/theorise how a society chooses to react to a whip. Put differently, there is a way to theoretically rectify the problématique of why societies react in certain ways and not others, filling in this arguably missing theoretical step of UCD. In fact, it is already embedded in Trotsky’s original coinage of UCD: ‘backwardness’.

Backwardness has been condemned as outdated even by UCD scholars because the term seems to suggest a normative ranking of developmental stages between different societies. ⁸⁸ Yet, what Trotsky actually argues is that backwardness relies on one’s perception of the self, where how one finds oneself to be backward is ‘arbitrary yet historically conditioned’ through interactions with other societies. ⁸⁹ Instead of being used as a term to categorise or rank societies, Trotsky understands backwardness as the self-perception of backwardness, referring strictly to the experience of facing threats to one’s external independence. Thus, this understanding of backwardness can capture how a society changes following a whip: precisely where the relevant agents perceive the society to be backward – whether that be its economic structure, military capabilities, or literary fashion – is where they will augment transformations in attempting to catch up. This is the necessary bridge between the ‘whip’ on the one hand and its corresponding changes within a society on the other hand.

But why is backwardness relevant here? Are we not talking about the origins of imperialism, what is usually conducted by the most economically dominant nations? Let us return briefly to the discussion of unevenness above. While there was indeed a well-known West-other unevenness, from which one can expect waves of self-perceived backwardness arising in non-Western societies, there was also unevenness between the first reaper of capitalism that was Britain and its near neighbours as well. As such, backwardness was not an experience exclusive to the colonised but also, in a different but very much relevant timeline, to the (would-be) colonisers. Indeed, experiences of self-perceived backwardness in France, Italy, Germany and Japan during the late 19th century have been diversely discussed. ⁹⁰

Backwardness is a useful framework that can capture the historical specificity of the diverse reactions to late-19th-century international unevenness among would-be colonisers, including those relevant to the explosion of empires during this period. Importantly, one can incorporate, in a historically sensitive way, the competing and copying dynamics that Adelman and Suzuki highlight. What I mean by this is that, on the one hand, it is true that these strategies had of course been present well before the late 19th century, capturing inter-imperial strategies that are perhaps transhistorical. On the other hand, however, UCD’s use of self-perception of backwardness induced by unevenness, from which relevant actors can choose to overcome by copying the ‘advanced’ and competing with them, provides a way to contextualise these strategies that can be observed trans-historically into historically specific developments in the late 19th century, contingent on, among others, the configuration of unevenness and the agents at play during this time.

With this second step of backwardness in the UCD causal sequence, the observation of unevenness has been operationalised to be of consequence towards processes within each imperial metropole. Specifically, the awareness of heightened unevenness, concretised through the whip, induced historically specific self-perceptions of backwardness that would shape how ‘catching up’ is conducted. And among them, there were sites of ‘catching up’ that would be consequential towards the outburst of empires.

Combination and development

Subsequently, what UCD captures in its concept of ‘combination’ is that in attempting to catch up, the self-perceived backward society grafts whatever it considers as ‘advanced’/’non-backward’ onto its pre-existing processes. Furthermore, it does so without having to go through the intermediate steps through which those so-called advances were obtained – this is what Trotsky terms the ‘privilege of historic backwardness’. ⁹¹ This results in changes that take on characteristics of both pre-existing structures and elements derived from elsewhere – hence the Trotskyist ‘combination’. ⁹² Here, thanks to our (re-)insertion of the concept of backwardness above, instead of filtering through countless possible combined transformations to find relevant ones to explain the origins of late-19th-century imperialism, self-perceptions of backwardness provide a theoretical starting point for such a search.

Importantly and as is already implied, because backwardness can capture a wide range of reactions to the whip, it follows that combinations can take place in diverse parts of society. This is emphasised because I argue that there is nothing about the concept of combination that limits itself to capture only the macro-level societal changes that UCD theorists have compellingly shown. The clearest example is Trotsky’s original formulation itself, where he argues that the international deeply influenced the Russian class structure and trajectory, culminating in a revolution that placed the proletariats, not the bourgeoisie, into power. The combination at play here is the distinct Russian class structure that carried out a historically unique revolution – indeed a macro- or societal-level combination. Applications of UCD in IR have mainly functioned at this society-wide level (class-based and otherwise) as well, focusing on subjects such as state formation, ⁹³ economic development ⁹⁴ or the rise of nationalism and other ideologies. ⁹⁵ However, as hinted at in the recent addition of an uneven and combined analysis of the modern Brazilian novel, ⁹⁶ UCD’s combinations are not limited to only these areas, however important they may be.

This argument is relevant here because imperial expansion is in the end a set of political decisions, usually made by the highest level of policymakers. As such, what needs to be explained will be the uneven and combined political decision-making behind them, that is, how the statesmen of the imperial metropoles constructed imperial justifications and policies in reaction to heightened international unevenness. This does not mean that the mentioned society-wide combined processes such as economic development or the formation of nationalist ideals had nothing to do with late-19th-century imperialism: of course they did. However, as important as these other processes were, they were still ‘filtered’ through the political decision-making process before becoming actual imperial policies. ⁹⁷ Reducing imperialism to any of its cognate processes, however influential they were, has already been demonstrated to be problematic: the economic determinism of the Hobson-Lenin itself is a readily available example.

Through the concept of combination, then, this UCD-based theory of late-19th-century imperialism can capture the diverse and complex outcomes of the heightened unevenness of this period as already highlighted by the above international turn: from ‘civilising’ projects to using foreign territories as diplomatic bargaining tools, and from using colonial control to protect routes to existing markets to pre-empting rival expansions by seizing them first. The most highlighted examples among these historically unique imperialistic combinations can be found in the imperial decisions of the late empires such as Germany, Italy and Japan, all of which augmented many of their imperial projects before they had the capacities to reap the economic benefits of possessing colonies. Only through understanding how these decisions were uneven and combined, that is, that they were enabled and/or accelerated by how the different vectors of unevenness became more frequent and intense during this period, can we make sense of them. In turn, these combined political decisions culminated in the global ‘development’ that was the ‘age of empire’.

A UCD-based theory of late-19th-century imperialism

In the simplest terms, then, what exactly is this UCD-based theory of the origins of late-19th-century imperialism? This meso-theory posits that during the late 19th century, heightened unevenness not only between the West and the East but also between Britain and other Western nations, which was driven by capitalism, triggered waves of self-perceived backwardness, namely in France, Germany, Italy, Russia and Japan. Responding to this unevenness and in attempting to ‘catch up’, these societies devised well-known combined imperialistic reactions: from ‘civilising’ projects to using foreign territories as diplomatic bargaining tools, and from using colonial control to protect routes to existing markets to pre-empting rival expansions by seizing them first. These imperialistic combinations were unique to each, depending on whatever pre-existing socio-political processes that were already taking place. This, of course, was not a one-off event: once ‘catching up’ propelled these late developers, they also disrupted the overall configuration of unevenness, causing even previously ‘advanced’ nations like Britain to experience self-perceived backwardness and consequently participated more extensively in the imperial ‘game’.

Let us explicitly assess this theory against the criteria set out before the section. First, is it a theory with an explicit causal sequence? Yes: in fact, I have argued that the reinstating of backwardness into UCD makes its micro-foundations even tighter. Furthermore, as compared to, for example, Waltz’s observation that unbalances of power have always produced imperialisms, which says little about the diversity of the different forms of imperialism across time and space that can only be accounted for with further examinations of the internal processes within each imperial metropole, these micro-foundations allows UCD to capture the actual mechanisms through which unevenness is connected to imperial foreign policymaking. Second, does it incorporate the significance of the international in this causal sequence? Yes: international unevenness is in fact the starting point of all applications of UCD. Lastly, does it allow for historically specific theorising, which includes recognising the significance of the historical development of capitalism during the 19th century? Yes: its need to always historicise the configuration of international unevenness in different contexts allows UCD to incorporate how the culmination of capitalism in certain places disproportionately empowered certain actors in world politics, mainly in Britain and the West broadly. Nonetheless, its strength of contextual sensitivity, I argue, does not hamper UCD’s overall parsimony: any of its application simply needs to stick with unevenness, the whip, backwardness, combination, and development as the starting anchors, from which historical complexities can be better grasped.

Conclusion

Despite a burgeoning international turn that has significantly advanced the study of the origins of late-19th-century imperialism, investigations into the topic have still been limited by either thick and supposedly atheoretical descriptions or a lack of historical specificity in theorising. Towards rectifying these issues to further this fruitful international turn, this article proposes a UCD-based theory of late-19th-century imperialism.

With this theory in place, the proposed next step is to continue the international turn’s re-writing of the origins of the ‘age of empire’, but now with the theoretically explicit language of UCD. Once the emergence of each empire is logically made sense through UCD’s conceptual toolkit of unevenness, the whip, backwardness, combination and development, we will complete the international turn’s account for this important epoch. ⁹⁸

As such, this article’s main contribution differs in one perhaps small but nonetheless critical way compared to a standard theory article in IR. As opposed to critically assessing existing theories from within the discipline ⁹⁹ or importing theories from elsewhere, its main objective has been to ask: what if IR’s existing international social theories can already contribute to debates beyond its disciplinary confines? In this case specifically, I have argued that recent innovations in the particular international social theory of UCD can help to innovate the trans-disciplinary international turn on the origins of late-19th-century imperialism. Perhaps we can already begin to, carefully but firmly, rectify the theory export-import imbalances that have long put IR’s disciplinary identity in crisis?

Furthermore, while explaining the origins of late-19th-century imperialism is seemingly antiquarian in scope, the article also contributes to three contemporary debates in IR. First, IR has only recently started to seriously engage with the effects of the long 19th century towards contemporary international relations. ¹⁰⁰ Correctly grasping the origins and nature of the empires that bookended this period would allow a firmer understanding of the foundations from which modern international order arose. The fact that the 19th century ended with not a world of nation-states but instead a world of formal empires mattered. What I mean by this is that while it is equally important to focus on unequal economic relations that may or may not have led to formal imperialism, ¹⁰¹ formal colonisations have had colonial and postcolonial trajectories of their own. Second, this article’s focus on how to satisfactorily bring in the international to explain imperialism under the capitalist epoch finds echoes in parallel attempts to understand the evolving forms of imperialism in the contemporary world, found especially in contemporary Marxist literature. ¹⁰² Lastly, the continuing advances of the UCD research programme under the banner of ‘multiplicity’ towards becoming the common ground of the discipline of IR, ¹⁰³ I argue, requires rigorous testing for how the theory is operationalised in different subjects of inquiry. This article’s main subject – imperial policymaking – differs from the mentioned typical themes of UCD, and thus has provided a useful opportunity to critically engage with and refine its framework, especially the concepts of backwardness and combination.