Hitler's dictatorial rule of Germany, which led to the deaths of millions in World War II, has placed him among history's most-hated villains. A decorated veteran of World War I, Adolf Hitler joined the German Workers' Party in 1919, later renaming it the National Socialist German Workers Party (shortened to Nazi). By 1921 he was the leader of the group, and in 1923 led an unsuccessful attempt to overthrow the ruling German Weimar Republic. Sentenced to prison for his role, Hitler wrote his manifesto, Mein Kampf, and emerged less than a year later as a populist spokesman for economically depressed and nationalistic Germans. Made chancellor in 1933, he suspended the constitution, forcibly suppressed all political opposition and brought the Nazis to power. He enforced policies with a brutal secret police (the Gestapo) and formed concentration camps for the organized murder of Jews, Gypsies and political opponents. Hitler's aggressive foreign policy precipitated World War II in 1939. Although he had remarkable early success in the war, by 1942 the tide had turned. Hitler apparently committed suicide in an air-raid shelter in Berlin in 1945, after Allied forces invaded Germany.

As a member of the Bolshevik party, Stalin (his adopted name meaning "Man of Steel") had an active role in Russia's October Revolution in 1917. He manuevered his way up the communist party hierarchy, and in 1922 was named General Secretary of the Central Committee. By the end of the 1920s Stalin had consolidated power and was the de facto leader of the Soviet Union. In the 1930s Stalin summarily executed his political enemies and started agressive industrial and agricultural programs that left untold thousands of peasants dead. During World War II Stalin was the commander of the Soviet military, and attended the postwar conferences at Yalta, Teheran and Potsdam. After Stalin's death he was denounced by his successor, Nikita Khrushchev, and "Stalinism" was officially condemned.

Roosevelt managed to pull Americans out of the Great Depression and lead them to victory in World War II, two pretty tall orders. His support of an active federal government shaped American politics through the remainder of the 20th century. His package of federally-supported public works and social programs was known collectively as the New Deal. Roosevelt was so popular he was elected four times -- a lengthy run which led to the passage of the 22nd Amendment, restricting presidents to two terms. He died in office only a few months into his fourth term. His successor was Harry Truman.

In the 1930s Hideki Tojo fought in the Sino-Japanese war, leading Japanese forces in occupied Manchuria. He returned to Tokyo in 1940 and held ministerial posts, where he urged an alliance with Germany and Italy against the Allied forces. Tojo became Prime Minister in 1941 and within two months ordered a surprise attack on U.S. naval forces in Hawaii. He served as the political and military leader of Japan until 1944, when it was clear the direction of the war had changed. After the war the Allies found Tojo guilty of war crimes and hanged him.

Soldier, politician and finally Prime Minister, Winston Churchill became one of Britain's greatest 20th-century heroes. Churchill fought with the British Army in India and Sudan, and as a journalist was captured in South Africa (where his dispatches from the Boer War first brought him to public prominence). He became a Member of Parliament in 1900. His early topsy-turvy political career earned him many enemies, but his stirring speeches, bulldog tenacity and his refusal to make peace with Adolf Hitler made him the popular choice to lead England through World War II. One of history's most quotable wits, Churchill wrote many histories, biographies and memoirs, including the landmark four-volume A History of the English-speaking Peoples (56-58). In 1953 he was awarded the Nobel Prize in Literature; he was knighted the same year.