Rudolf Vrba

Deported to Auschwitz as a teenager in 1942, Vrba escaped in April 1944 and co-wrote the Vrba-Wetzler report, the first detailed account of the camp's gas chambers to reach the outside world, describing exactly how the Germans were murdering people rather than "resettling" them. Distributed to Western governments, it is credited with helping halt the mass deportation of Hungary's Jews to Auschwitz that July, saving more than 200,000 lives. He later became a working biochemist in Britain and Canada.