As a member of a reserve battalion during the First World War, Himmler did not see active service or combat. Having joined the Nazi Party in 1923 and the SS in 1925, he was appointed Reichsführer-SS by Adolf Hitler in 1929. Over the next sixteen years, Himmler developed the SS from a 290-man battalion into a million-strong paramilitary group. He was known for good organisational skills and for selecting highly competent subordinates, such as Reinhard Heydrich in 1931. From 1943 onwards, he was both Chief of the Kriminalpolizei (Criminal Police) and Minister of the Interior, overseeing all internal and external police and security forces, including the Gestapo (Secret State Police). He also controlled the Waffen-SS, the military branch of the SS.
