Simeon I of Bulgaria was the first Bulgarian Tsar and the first person who has borne the title "Tsar".[1]
Reception of the Tsar of Russia in the Moscow Kremlin
Crowning of Dušan, emperor of Serbia, for Tsar.

Tsar (ɑːr/ or ɑːr/; Old Church Slavonic: ц︢рь [usually written thus with a title] or цар, царь), also spelled czar, or tzar, is a title used to designate East and South Slavic monarchs or supreme rulers of Eastern Europe, originally Bulgarian monarchs from 10th century onwards. As a system of government in the Tsardom of Russia and the Russian Empire, it is known as Tsarist autocracy, 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.[2] Simeon II, the last Tsar of Bulgaria, is the last person to have borne the title Tsar.

Meaning in Slavic languages

The title Tsar is derived from the Latin title for the Roman emperors, Caesar.[3] In comparison to the corresponding Latin word "imperator", the Byzantine Greek term basileus was used differently depending on whether it was in a contemporary political context or in a historical or Biblical context. In the history of the Greek language, basileus had originally meant something like "potentate". It gradually approached the meaning of "king" in the Hellenistic Period, and it came to designate "emperor" after the inception in the Roman Empire. As a consequence, Byzantine sources continued to call the Biblical and ancient kings "basileus" even when that word had come to mean "emperor" when referring to contemporary monarchs (while it was never applied to Western European kings, whose title was transliterated from Latin "rex" as ῥήξ, or to other monarchs, for whom designations such as ἄρχων "leader", "chieftain" were used).

As the Greek "basileus" was consistently rendered as "tsar" in Slavonic translations of Greek texts, the dual meaning was transferred into Church Slavonic. Thus, "tsar" was not only used as an equivalent of Latin "imperator" (in reference to the rulers of the Byzantine Empire, the Holy Roman Empire and to native rulers) but was also used to refer to Biblical rulers and ancient kings.

From this ambiguity, the development has moved in different directions in the different Slavic languages. Thus, the Bulgarian language and Russian language no longer use tsar as an equivalent of the term emperor/imperator as it exists in the West European (Latin) tradition. Currently, the term tsar refers to native sovereigns, ancient and Biblical rulers, as well as monarchs in fairy tales and the like. The title of king (Russian korol' , Bulgarian kral- the origin of which is Charlemagne (Karl)) is sometimes perceived as alien and is by some Russian-speakers reserved for (West) European royalty (and, by extension, for those modern monarchs outside of Europe whose titles are translated as king in English, roi in French etc.). Foreign monarchs of imperial status, both inside and outside of Europe, ancient as well as modern, are generally called imperator (император), rather than tsar.

In contrast, the Serbocroatian language (which can also be viewed as different languages—Serbian, Croatian and Bosnian) translate "emperor" (Latin imperator) as tsar (car, цар) and not as imperator, whereas the equivalent of king (kralj, краљ, король) is used to designate monarchs of non-imperial status, Serbian as well as foreign ancient rulers—like Latin "rex". Biblical rulers in Serbian are called цар and in Croatian kralj.

In the modern West Slavic languages and Slovene language, the use of the terms is nearly identical to the one in English and German: a king is designated with one term (Czech král, Slovak kráľ, Polish król, Slovene kralj), an emperor is designated with another, derived from Caesar as in German (Czech císař, Slovak cisár, Polish cesarz, Slovene cesar; Croatian cesar and Montenegrin ćesar fell into disuse after World War I), while the exotic term "tsar" (Czech, Slovene and Polish car, Slovak cár) is reserved for the Bulgarian, Russian and Serbian rulers.

In the Polish language however tsar is used as an equivalent to imperator, never as king. The term tsar is always used to refer to the Russian rulers before Peter the Great, and very often to those succeeding.

Other Languages
Afrikaans: Tsaar
Alemannisch: Zar
العربية: تسار
asturianu: Zar
azərbaycanca: Çar
تۆرکجه: تزار
বাংলা: জার
Bân-lâm-gú: Sa-hông
беларуская: Цар
български: Цар
català: Tsar
Чӑвашла: Патша
čeština: Car
dansk: Zar
Deutsch: Zar
eesti: Tsaar
Ελληνικά: Τσάρος
español: Zar
Esperanto: Caro
euskara: Tsar
فارسی: تزار
français: Tsar
Frysk: Tsaar
Gàidhlig: Tsar
galego: Tsar
한국어: 차르
հայերեն: Ցար
हिन्दी: त्सार
hrvatski: Car
Ido: Caro
Bahasa Indonesia: Tsar
interlingua: Tsar
italiano: Zar
עברית: צאר
Jawa: Tsar
ქართული: ცარი
қазақша: Патша
Kiswahili: Tsar
kurdî: Çar
Latina: Tzar
latviešu: Cars
lietuvių: Caras
Lingua Franca Nova: Tsar
magyar: Cár
македонски: Цар
മലയാളം: സാർ
मराठी: झार
مصرى: تسار
Bahasa Melayu: Tsar
Nederlands: Tsaar
日本語: ツァーリ
norsk: Tsar
norsk nynorsk: Tsar
occitan: Tsar
oʻzbekcha/ўзбекча: Sar
پنجابی: زار روس
polski: Car
Ποντιακά: Τσάρος
português: Czar
română: Țar
русиньскый: Царь
русский: Царь
Scots: Tsar
shqip: Cari
sicilianu: Zar
Simple English: Tsar
slovenčina: Cár
slovenščina: Car
српски / srpski: Цар
srpskohrvatski / српскохрватски: Car
suomi: Tsaari
svenska: Tsar
Tagalog: Tsar
татарча/tatarça: Патша
ไทย: ซาร์
Türkçe: Çar
українська: Цар
اردو: زار
Tiếng Việt: Sa hoàng
Winaray: Tsar
粵語: 沙皇
中文: 沙皇