The Cyrillic spelling is more phonetic, so the tz or cz sounds are very close, therefore the acceptance of either spelling. Kind of like the letter "c" can either be hard or soft in the english language.

Well, here's what my research turns up. Pretty interesting. Tsar ...., occasionally spelled Czar or Tzar and sometimes Csar or Zar in English, is a Slavonic term designating certain monarchs. Originally, and indeed during most of its history, the title tsar meant Emperor in the European medieval sense of the term, i.e., a ruler who has the same rank as a Roman or Byzantine emperor due to recognition by another emperor or a supreme ecclesiastical official (the Pope or the Ecumenical Patriarch). Occasionally, the word could be used to designate other, non-Christian supreme rulers. In Russia and Bulgaria, the imperial connotations of the term were blurred with time and by the 19th century it had come to be viewed as an equivalent of king. The modern languages of these countries use it as a general term for a monarch. "Tsar" was the official title of the supreme ruler in the following states: Bulgaria in 913–1018, in 1185-1422 and in 1908–1946 Serbia in 1346–1371 Russia from about 1480 (or 1547) until 1721 (after 1721 and until 1917, the title was used officially only in reference to the Russian emperor's sovereignty over certain formerly independent states such as Poland and Georgia) http://www.dailykos.com/story/2007/4/13/82450/0121 I also found this: The "tsar"/"czar" business is again from when people didn't care. "Tsar'" is short for "Tsesar'," that is, "Caesar." (These guys took the title "tsar'" precisely to avoid being kings and instead to proclaim their imperial pretensions.) Even into the 20th century, the Tsar's son was called not just "Tsarevich" but also "Tsesarevich." Anyway, in olden times when people didn't care, "Caesar" to "Csar" to "Czar" is an easy set of hops. As for the German "Kaiser," that's the German form of "Caesar" too, and that's even easier — we're inclined to keep the spelling of something originally written in the Latin alphabet. http://volokh.com/posts/1181607555.shtml Neither of these are from any dictionary. I found it quite interesting. I had no idea Tsar or Kaiser literally translated out to Caesar.

I personally spell it Czar.

I don't think there is ever a "correct" spelling of a term or place name when you're using a different alphabet than the original language of the term. You have to resort to a phonetic approximation, which is then up to interpretation, which tends to change over time. Beijing used to be called Peking -- the name of the city didn't change, just the accepted English spelling in an attempt to create the most accurate pronunciation. In the instance of Czar/Tsar, I only would use the latter spelling in crossword puzzles. What bugs me more is when US Government officials are appointed with the title of "Czar". I want to look at their business cards to see if it really shows their job title as "Drug Czar", or whatever. And wouldn't creating an official with the title of "Czar" seem to put them in authority over all elected officials? Who started this crazy lingo? Enough of my rant for the day!

I spell it Czar, I was taught that way.

I always went with Tsar and strangely enough in a Clive Cussler book I was reading today it said that Tsar means Caesar :o)

I use, and have seen it from my professors 'Czar' :) hope it helps.

In the UK we spell it Tsar, so that would be my contribution. Incidentally it wasn't a communist revolution, but a Bolshevik revolution.