Tsarist period

Tsar (/zɑːr/ or /tsɑːr/) (Old Church Slavonic: ц︢рь [usually written thus with a title] or цар, цaрь), also spelled csar, or czar, is a title used to designate East and South Slavic monarchs or supreme rulers of Eastern Europe. As a system of government in the Tsardom of Russia and the Russian Empire, it is known as , or Tsarism. The term is derived from the Latin word Caesar , which was intended to mean "Emperor" in the European medieval sense of the term—a ruler with the same rank as a Roman emperor, holding it by the approval of another emperor or a supreme ecclesiastical official (the Pope or the Ecumenical Patriarch)—but was usually considered by western Europeans to be equivalent to king, or to be somewhat in between a royal and imperial rank.

"Tsar" and its variants were the official titles of the following states:

The first ruler to adopt the title tsar was Simeon I of Bulgaria.Simeon II, the last Tsar of Bulgaria, is the last person to have borne the title Tsar.

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