Josef Mengele was born on March 16, 1911. Growing up as a Bavarian child, those who knew him described him as intelligent, ambitious, and well liked-not at all the sadistic murderer that he would become. At the age of 20, Mengele signed up to become an SA (Nazi storm trooper) and the next year to be a member of the SS. He quickly rose through the ranks and it is said that he met famous Nazi officers such as Alfred Rosenberg, the former Chief Nazi ideologist, and Hitler himself. Mengele's biggest role come when he was stationed in Auschwitz in May 1943.