History's greatest monsters

Dictators responsible for massive crimes against humanity (over 20 million dead)

Name Country Time in Power Regime type Notable Events After...
Joseph Stalin USSR 1924-1953 Communist Revolutionary regime died in office
Adolph Hitler Germany 1933-1945 Fascist World War II, Jewish Holocaust committed suicide
Mao Tse-Tung China 1945-1976 Communist Revolutionary regime died in office

Dictators responsible for horrible atrocities (at least 1 million dead)

Name Country Time in Power Notable Events Regime type After...
King Leopold II Belgium 1865-1909 Colonization of the Congo Monarch died in office
Kaiser Wilhelm II Germany 1888-1918 World War I Monarch fled, died in exile
Czar Nicholas II Russia 1894-1917 World War I Monarch overthrown, killed
Enver Pasha, member of triumvirate dictatorship Turkey 1913-1918 Armenian genocide Military fled, died in rebellion
Vladimir Lenin USSR 1917-1924 Russian Civil War Communist died in office
Emperor Hirohito Japan 1926-1989 World War II Monarch died in office
Prime Minister Hirota Koki 1936-1937 Military resigned, tried, executed
Prime Minister Tojo Hideki 1941-1944 Military resigned, tried, executed
President Chiang Kai-shek China / Taiwan 1928-1949 Chinese Civil War Military died in office
President Ho Chi Minh North Vietnam 1945-1969 Vietnam War Communist died in office
President Kim Il Sung North Korea 1948-1994 Korean War Communist died in office
President Yahya Khan Pakistan 1969-1971 Indo-Pakistan War Military resigned, died
President Saddam Hussein Iraq 1969-2003 Iran-Iraq War, Kurdish genocide one party state overthrown, tried, executed
Prime Minister Pol Pot Cambodia 1975-1979 Cambodian genocide Communist overthrown, arrested, died awaiting trial
President Kim Jong Il North Korea 1994- chronic famines Communist still in power

Generally bad dictators (over 10,000 killed)

President Kemal Ataturk Turkey 1920-1938 one party state died in office
Prime Minister Benito Mussolini Italy 1922-1943 Fascist overthrown, killed
Prime Minister Antonio de Salazar Portugal 1932-1968 Fascist resigned, died
Francisco Franco Spain 1939-1975 Fascist died in office
Prime Minister Ion Antonescu Romania 1940-1944 Fascist overthrown, tried, executed
Ante Pavelic Croatia 1941-1945 Fascist overthrown, died in exile
Gheorghe Gheorghiu Romania 1945-1965 Communist died in office
President Tito Yugoslavia 1945-1980 Communist died in office
President Yakubu Gowon Nigeria 1966-1976 Military overthrown, still living
President Suharto Indonesia 1967-1997 Military resigned, still living
President Idi Amin Uganda 1971-1980 Military overthrown, died in exile
President Mengistu Haile Ethiopia 1974-1991 Communist fled, lives in exile
President Le Duan Vietnam 1976-1986 Communist died in office
President Babrak Karmal Afghanistan 1979-1987 Communist resigned, died in exile
President Slobodan Milosevic Yugoslavia 1997-2000 Fascist resigned, arrested, died awaiting trial
President Omar al-Bashir Sudan 1989- Military Still in office