Adolf Hitler was the leader of Nazi Germany from 1933 to 1945. He came to power in 1933 and implemented policies that led to the persecution and genocide of millions of people, primarily Jews, but also other minority groups such as homosexuals, Romani, people with disabilities, and political opponents. Hitler's leadership led to the outbreak of World War II, and his aggressive expansionist policies were a major factor in the devastation and loss of life that occurred during the war. Hitler's leadership was characterized by totalitarianism, anti-Semitism, and aggressive expansionism. He committed numerous war crimes and crimes against humanity, including the Holocaust, which resulted in the systematic extermination of six million Jews and millions of others.