Adolf Hitler brought the Nazi party to prominence in Germany, initiated the Holocaust and started World War II. He was responsible for the deaths of millions, including soldiers in the war and civilians killed in Nazi concentration camps.
Hitler fought for the Germans during World War I, and he was dismayed with the destruction of Germany from the sanctions levied in the Treaty of Versailles. He rose to power in the National Socialist German Workers Party, which was an extremely nationalistic political party that sought to restore Germany to its previous position as a world power. He used his position atop this party and the dire economic situation of Germany to stir up public sentiment against foreigners, Jews and other groups that he blamed for Germany's collapse.
The public fervor allowed him to conscript German forces for the first time since the end of World War I. He invaded part of Poland and began sending civilians to concentration camps, where they faced hard labor, awful conditions and often death. As he sought to expand Germany's control over Europe, much of the rest of the world entered the war. Hitler would eventually capture huge swaths of Europe, including Poland and France. However, the surrender of Japan, the influx of American forces into Europe and an ill-advised attempt to invade Russia led to the downfall of his forces. Facing certain defeat, Hitler committed suicide in his bunker in 1945.