Who did hitler first kill?

Answer 1

He didn't, the Holocaust was not instigated by Hitler. It was without a doubt done in his name, but his personal involvement was minimal.

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The above is rather off topic and highly misleading, though it is true that Hitler was not involved in the detailed planning. The driving force behind Nazi antisemitism was Hitler's own frenzied, obsessive and fanatical antisemitism. From the start of World War 2 he was, increasingly, gripped by the bizarre notion that "the Jews" had plunged Germany into war. In reality, he himself had started World War 2 in Europe.

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Now, to answer the question. Systematic mass killings of Jews began in June 1941. However, some Jews had been killed much earlier by the Nazis, starting on a relatively small scale in 1933.

Answer 2

The Mentally ill. Though different individuals died in the concentration camps, or protective custody, the first group to recieve an official death sentence was the mentally disabled.

Answer 3

If we don't count Crystallnacht, he was 50 years old. (In 1939, when he invaded Poland, and the first murders of Jews in the Holocaust took place.)

Answer 4

His wife