Tsar is a title for the supremeruler in several countries.
InBulgaria, the title was used in 913–1422 and again in 1908–1946. The last tsar to ruleBulgaria wasBoris III, who replacedFerdinand I of Bulgaria 1918.
InSerbia, the title was used in 1346—1371. The last tsar to rule Serbia wasStephen Uroš V.
In theRussian Empire, the title was used from 1546 until 1721. Starting in 1721, the title of Russian emperors wasimperator, but the wordtsar remained in common use until theRussian Revolution in 1917. The last tsar to ruleRussia wasNicholas II, who replacedAlexander III in 1894. The system of government used during theTsardom of Russia and theRussian Empire was calledTsarist autocracy, also known as Tsarism.
Tsar is also spelledtzar,czar, andcsar. It is theEastern European word forcaesar. It can be translated toemperor.
