when did his nazi career begin?
In 1923.
Heinrich Himmler
Heinrich Luitpold Himmler (; 7 October 1900 – 23 May 1945) was "Reichsführer" of the "Schutzstaffel" (Protection Squadron; SS), and a leading member of the Nazi Party (NSDAP) of Germany. Himmler was one of the most powerful men in Nazi Germany and a main architect of the Holocaust.

As a member of a reserve battalion during World War I, Himmler did not see active service. He studied agronomy in university, and joined the Nazi Party in 1923
what is the night of the long knives? A purge took place in Nazi Germany. can you tell me something about their ideology? Nazism. where did it get its name from? The word "Nazi" was a hypocorism of the German male name "Igna(t)z". when did the purge take place? June 30 to July 2, 1934. who were its commanders? Ernst Röhm, Hermann Göring and Heinrich Himmler. what was the role of the second person in the ww i ? He served with his infantry regiment in the area of Mülhausen. what part did he play in the reichstag fire? He was one of the first to arrive on the scene. what can you tell me about the third person? He was one of the most powerful men in Nazi Germany and a main architect of the Holocaust.
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Heinrich Himmler [SEP] Introduction
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 German Police and Minister of the Interior, overseeing all internal and external police and security forces, including the Gestapo (Secret State Police). He controlled the Waffen-SS, the military branch of the SS. Due to his lifelong interest in occultism, Himmler interpreted Germanic neopagan and "Völkisch" beliefs to promote the racial policy of Nazi Germany and incorporated esoteric symbolism and rituals into the SS. Himmler formed the "Einsatzgruppen" and built extermination camps. As overseer of the Nazi genocidal programs, Himmler directed the killing of some six million Jews, between 200,000 and 500,000 Romani people, and other victims.