Two figures loom large over historical sociology in the English language at the end of the last century: Charles Darwin and Karl Marx.

This speaks to a tension at the heart of the discipline – between the grand systems of Marxism, which harken to an Aristotelian teleology of time, on the one hand, and the contextual variation and selection of Darwinian evolution, which overthrew Aristotelian teleology with an empirically grounded, and contextually sensitive, theory of change.
Baked into Darwin’s original idea of evolution, I found from reading early drafts of Origin of Species in the U.L. Rare Books Room, is the idea of context – specifically, environmental context. Organisms’ survival depends on adapting to the environment in which they find themselves. My use of the term ‘context’ may seem prima facie ahistorical, but Darwin himself takes pains to ‘repeat […] the ‘analogical’ or ‘adaptive’ resemblances between organic beings’; ‘It follows from our theory, that the orders must have descended from one common stock of an immeasurably [ancient?] epoch’. The use of ‘analogy’ as an analogy to ‘adaptation’ is not the only textual aspect of Darwin’s thought, which echoes Goethe’s fascination with ‘elective affinities’ in depicting the ‘affinity’ among isolated groups of species. Being well-read himself, Darwin cites Malthus’ theory of population as a central inspiration behind the theory of evolution, while Mendel’s prototype of today’s genetic biology passed Darwin by.
Reading Darwin through, and into, the disciplines of historical sociology and intellectual history is not, therefore, out of step with the spirit of Darwin. Is it ahistorical, then, to read historical sociology through Darwin?
On the surface, historical sociologists Michael Mann, Charles Tilly, Hendrik Spruyt, Adam Watson, and W. G. Runciman do not have much in common, besides their shared discipline. The idea of evolution as central to historical sociology is certainly not explicitly acknowledged by all five of these pivotal theorists. Michael Mann, who pioneered the subdivision of social power into economic, military, ideological, and political components, positions the beginning of his story in ancient Mesopotamia as ‘the end of general social evolution.’ But he goes on to emphasise the centrality of competition among empires and city-states in the ancient world and nation-states in the modern world as the driver of technological development, and of the emergence (if it is too soon to use the term ‘selection’) of institutions that are adapted to this environment of intense resource competition. Perhaps Mann’s ‘end of general social evolution’ represents the beginning of a particular theory of social evolution in the context of competing societies through history. One analogy for The Origin of Species, then, is Mann’s Sources of Social Power (published in four volumes from 1981). Each source, Mann argues, comprises overlapping networks of power with multiple nodes, jostling for ideological or material dominance over institutions. This theory, which Mann traces to the classical sociology of Max Weber, owes a great deal to Darwin, although not, it seems, to Marx, who Mann decisively rejects as giving a teleological and reductionist theory of history.
Charles Tilly builds his theory from the ground up, arguing that early-modern European states competed for power through warfare, which favoured bureaucracy and the market over premodern institutions of state power; hence the title of Tilly’s 1992 book, Coercion, Capital, and European States. Like Mann, Tilly gives an implicitly Darwinian theory of historical change, with Darwin’s animating concepts of variation and selection playing clear conceptual roles. States vary like species do; and their survival is at stake. Hence, the pressure of competition leads some states to survive, and their institutions to be selected for over others. The context of variation and the constraint of selection lead jointly to the historical reemergence of social evolution. Tilly acknowledges that historical sociology is similarly torn between generalising social theory and contextualising history, analogous to the two faces of evolution in Darwin: contextual variation, and natural selection. Tilly is also deeply influenced by Marx, whose concept of ‘bourgeois revolution’ (as he writes in a working paper from the late 1980s) is not altogether bankrupt, since elite competition indeed drove modern tumults. Tilly then notes Engels’ attribution of Marx’s findings to his reading of Darwin, which, while doubtful, is compatible with Marx’s own letters to Engels and Lassalle, as well as Marx and Darwin’s joint inspiration: Malthus, who Tilly also notes as central to Marx’s story, as well as Darwin’s. Running through these accounts are fears of population pressure and resource scarcity, which drove institutional competition and selection, where only one system could survive.
Tilly and Mann are therefore implicitly Darwinian. Hendrik Spruyt, W. G. Runciman, and Adam Watson all explicitly pay homage either to Darwin (in the case of Spruyt and Runciman) or to the idea of evolution as a paradigm for social change in general (in the case of all three). Spruyt explores what Marx referred to in Capital as ‘the evolution of trade’ in the early-modern period, specifically through the paradigm of elite competition over the fruits of trade, while Runciman frames war and trade as evolutionary pressures for selection over the fruits of institutional variation. Watson applies evolution to international society, thereby expanding our remit to international relations theory, which since the 1990s has wrestled with philosophical ideas of space and time.
How are these explicit and implicit ideas of evolution in historical sociology relevant to the discipline of intellectual history? At least one example bears considering. Eleven years before Michael Mann’s The Sources of Social Power, Volume I, was published, J. G. A. Pocock in The Machiavellian Moment considered how the concept of time has evolved through history, noting its secularisation from Aristotelian teleology through Augustinian theodicy to the despair of Machiavelli’s world in the wake of Dante’s Inferno. Rather than marking an ascent to paradise, the arrow of time headed downwards into the abyss of human vice, rewritten as virtù and the antitheological politics of statecraft. These threads run through the conclusion of Origin of Species: From the ‘great law of the multiplication of organisms not needed’, Darwin notes,
We cease to be astounded, that a group of animals should have formed to lay their eggs in the bowels […] of other […] beings, — that some animals live by, and even delight in cruelty – that animals should be led away by false instincts [..] for […] from death, famine and the struggle of existence, we see that the most exalted end, which we are capable of concerning, namely the creation of the higher animals, has directly proceeded […]
The language of ends seems antithetical to Darwin, who stands not only in the shadow of theodicy (opening Origin with pious quotations from Whewell and Bacon) but also in the shadow of Aristotelian teleology, referring on one occasion to the ‘final end’ of a plant’ as its ‘fruit’. But perhaps the idea of evolution, like Pocock’s Machiavellian Moment, involves a certain process of secularisation and a loss of mysticism, due in part to the empirical methodology which social sciences inherit from their naturalistic counterparts, but also due to the contextual theory at the heart of evolution.
In a survey of the field of social sciences from 1981, Filipe Van Parijs distinguishes evolution from functional explanations, which attribute events to a purpose or final cause. Historical sociology seems, broadly, to fit this rule, but bears an imprint of Aristotelian time in Darwinian context, which in historical sociology is both spatial and temporal, as shown by the shared debts to Weber’s territorial theory of the state and Marx’s time-concerned theory of labour and class struggle. Time and space denote scarce quantities of social matter, which can be measured in general terms, but which have particular limitations. No state, and no class, can rise forever without facing certain limiting conditions, as Machiavelli was so insistent on in the Discorsi. The idea of evolution is similarly limited in scope, but it ought to be. Social evolution is, I think, a shared concern among historical sociologists and intellectual historians, for whom ideas are as sensitive to context, and therefore potentially to the pressures of evolution, as are the states and classes which historical sociologists examine, and perhaps as were the species for whom Darwin sought an origin, marvelling – as we might with our own subjects of study
that from so simple an origin, through the selection of infinitesimal varieties, endless forms most beautiful and most wonderful have been evolved.