Himmler, Heinrich (1900–1945), a German Nazi leader. As head of the Nazi concentration camp system, he was largely responsible for the deaths of vast numbers of persons. Himmler was an early follower of Adolf Hitler. In 1929 he became leader of the SS (Nazi party police), in 1934 of the Gestapo (secret police), and in 1936 of the entire German police system. In 1943 during World War II he became minister of the interior, and after July, 1944, was almost the equal of Hitler in power. Himmler committed suicide after his capture by the British.