The transdisciplinary project of historical sociology is founded upon the premise that neither historiography nor social science can proceed, independently, to a full or sound explication of any collective human action. The mutual engagement of history and sociology is an analytical prerequisite for keeping in focus the simultaneity that determines the social constitution of historical events and processes, and the historical transformation of the agents, institutions and cultures that constitute the fluxional realities within which ‘history/social life’ is made. The epistemological challenges entailed in this joint venture are manifold: questions of evidence, concept-formation and theory must all be rethought so as to permit an integrative comprehension of the historical and the social, the diachronic and the synchronic.

Few scholars have contributed more to this enterprise than Michael Mann, who is producing a body of research celebrated both for the scope of its historical coverage and the nuanced deploy of its categories of interpretation. Attempting nothing less than a grand historical sociology of ‘world time’, Mann's immense yet still unfolding ‘canvas’ features a mixture of styles, ranging from the broader brush strokes of generalizing macro-narratives to more finely detailed renderings of selective sociohistorical processes. Mann's many-sided efforts to lay bare the ‘infrastructures of power’ that have shaped the epochal trajectories of change in world history thus provide an exemplary base from which to assess the research practices of historical social science.