In January 1942, nine European governments in exile, along with Britain and America, issued a joint declaration expressing their desire to use criminal law to punish those guilty of the atrocities of which news was now emerging from Nazi-occupied territories. A few days later, senior Nazis, meeting at Wannsee on the edge of Berlin, agreed on a ‘Final Solution’ for the Jews of Europe. From then until the end of the war, even as the Germans pursued their programme of extermination, Allied lawyers set about framing international laws to protect both individuals and groups from the ‘barbarity’ and violence of their own governments.

Two of these lawyers, Hersch Lauterpacht and Rafael Lemkin, came from Nazi-occupied Eastern Europe and both studied, though not at the same time, at the same law faculty. Philippe Sands’s grandfather Leon also grew up in the area, and all three spent time in the city of Lviv. Out of