Julian Jackson won the £5,000 (about $6,375) Pol Roger Duff Cooper Prize for historical work for France on Trial: The Case of Marshal Pétain. In addition to the cash award, the winner receives a magnum of Pol Roger champagne and a copy of Cooper's autobiography, Old Men Forget.
Described by the judges as "asking profound, historical questions about how to act in impossible circumstances," the book uses the 1945 trial of Marshal Pétain to explore collusion and its consequences in post-war France.
Chair of the judges Artemis Cooper called Jackson "one of those rare beasts, a rigorous historian with the skills of a seasoned novelist.... As you read, you are inside that hot, febrile courtroom where Marshal Pétain is being tried: grappling with moral dilemmas, and the testimony of Vichy administrators desperate to exonerate themselves. As for the old man on trial, is he a hero, a traitor, or both? Who needs a thriller when real events make such compelling reading?"