Peregrine’s research focuses on “big questions” of human history: Why did people come to live in cities? How do coercive leaders maintain their power? What happens when people from very different cultural and linguistic backgrounds come to live together? He has pursued answers to these questions in a variety of different ways—from archaeological excavation to complex cross-cultural statistical analyses. Most recently he has been doing comparative research with archaeological data trying to understand the preconditions that provide social resilience to catastrophic climate-related disasters. His current work, funded by the Army Research Office, uses the “atmospheric event” of A.D. 536 (which darkened the Northern Hemisphere for 18 months) as a model for effects of a limited nuclear war, and he is trying to understand the conditions that led some societies to collapse and others to flourish in the wake of this event.