In recent decades, accumulation has become a curiously neglected concept in imperial history. Despite this, it remains a powerful heuristic for understanding the drives, dynamics, and effects of modern imperialism. Juxtaposing early Marxist conceptualizations of accumulation with some formative historiographic debates about colonial knowledge in Africa and Asia, I argue that accumulation can provide a better account of the ‘lumpy’ spatiality of empire than the currently predominant model of the network. Its advantages stem from it being a concept inherently concerned with the relationship between appropriation and accrual. Using accumulation to frame the study of empire foregrounds the relationships between spaces of extraction and dispossession, and sites of aggregation and accretion. The lens of imperial networks struggles to attend to places of disconnection and asymmetries of power. In contrast, the concept of accumulation was developed precisely to better understand uneven distributions and the production of inequalities.