Joseph Stalin was the leader of the Soviet Union (Russia) from the mid 1920's to 1953. In this time, Stalin had upward of 20 million people killed. Adolf Hitler was the leader of the Nazi Party and Chancellor of Germany from 1933 to 1945. In this time period, Hitler had killed upward of 21 million people. Stalin may have been in power longer but Hitler had more people killed in less time. He also started World War 2, which Stalin would later enter in favour of Hitler. This ended when Hitler turned on him. Hitler's army spread throughout Europe and gained control of 85-90% of the country. After evaluating these facts you can see that Hitler was the cause of more deaths than Stalin.