As the successor to his father, Hafez, Bashar al-Assad has continued with his father's brutal rule of Syria.
Muammar al-Qaddafi seized control of the Libyan government in 1969, and ruled as an authoritarian dictator for more than 40 years before he was overthrown in 2011.
Jean-Bedel Bokassa was the president of the Central African Republic (1966-1976) and a self-proclaimed emperor of the Central African Empire (1976-1979).
Nicolae Ceausescu was the leader of Communist Romania for more than two decades until his execution in 1989.
Idi Amin was a Ugandan president best known for his brutal regime and crimes against humanity while in power from 1971-1979.
Ivan the Terrible, or Ivan IV, was the first tsar of all Russia. During his reign (1533-1584), Ivan acquired vast amounts of land through ruthless means, creating a centrally controlled government.
Kim Jong Il's dominating personality and complete concentration of power has come to define the country North Korea.
As Roman emperor, Nero’s reign was lavish and tyrannical. He killed his mother, persecuted Christians and is said to have "fiddled while Rome burned."
Pol Pot was the political leader of Cambodia who was responsible for the deaths of thousands of people under his reign.
Mobutu Sésé Seko was president of the Democratic Republic of the Congo, which was also known as Zaire for much of his reign, from 1965 to 1997.
Joseph Stalin ruled the Soviet Union for more than two decades, instituting a reign of terror while modernizing Russia and helping to defeat Nazism.
Mao Tse-tung was the principal Chinese Marxist theorist, soldier and statesman who led his nation's Cultural Revolution.