Sir Ian Kershaw is an English historian whose work has chiefly focused on the social history of 20th-century Germany. He is regarded by many as one of the world's foremost experts on Nazi Germany and noted for his biography of Adolf Hitler.
Kershaw worked at the University of Sheffield. He has called German historian Martin Broszat an "inspirational mentor" who did much to shape his understanding of Nazi Germany. Kershaw has served as historical adviser on numerous BBC documentaries, notably The Nazis: A Warning from History and War of the Century.