Russia, Soviet Union, Union of Soviet Socialist Republics, USSR - a former communist country in eastern Europe and northern Asia; established in 1922; included Russia and 14 other soviet socialist republics (Ukraine and Byelorussia an others); officially dissolved 31 December 1991

crowned head, monarch, sovereign - a nation's ruler or head of state usually by hereditary right

Aleksandr Pavlovich, Alexander I, Czar Alexander I - the czar of Russia whose plans to liberalize the government of Russia were unrealized because of the wars with Napoleon (1777-1825)

Alexander II, Alexander the Liberator, Czar Alexander II - the son of Nicholas I who, as czar of Russia, introduced reforms that included limited emancipation of the serfs (1818-1881)

Alexander III, Czar Alexander III - son of Alexander II who was czar of Russia (1845-1894)

Boris Fyodorovich Godunov, Boris Godunov, Godunov - czar of Russian (1551-1605)

Ivan IV, Ivan Iv Vasilievich, Ivan the Terrible - the first czar of Russia (1530-1584)

Czar Nicholas I, Nicholas I - czar of Russia from 1825 to 1855 who led Russia into the Crimean War (1796-1855)

Nicholas II - the last czar of Russia who was forced to abdicate in 1917 by the Russian Revolution; he and his family were executed by the Bolsheviks (1868-1918)

Czar Peter I, Peter I, Peter the Great - czar of Russia who introduced ideas from western Europe to reform the government; he extended his territories in the Baltic and founded St. Petersburg (1682-1725)