The historical novel is one of the most popular and critically significant genres of postcolonial writing, but, to date, almost no systematic scholarship is dedicated to it. This essay proposes theoretical and critical parameters for exploring this genre. It begins with the observation that plausibility is a key principle articulated by many postcolonial writers and explores how framing novels in these terms, as a kind of realism, requires readers to negotiate heterogeneous structures of reference—and, in particular, to read imaginary characters as abstractions of historical phenomena. The second half of the paper explores the theoretical implications of this ontological heterogeneity, suggesting how the genre’s conventions are inflected by normative patterns of gender, race, and temporality. Overall, I propose that it is possible to read the postcolonial historical novel as a kind of allegory, and I offer the term allegorical realism to describe this paradoxical mixing of conceptual and affective knowledge.