Here's a breakdown of the etymology:
* Caesar: The title of the Roman emperors, most famously Julius Caesar.
* Tsar: The Slavic adaptation of "Caesar," adopted by the rulers of Bulgaria in the 9th century and later by the rulers of Russia in the 16th century.
* Czar: The English spelling of "tsar," which became popular in the West during the reign of the Russian tsars.
The title "tsar" was used as a way to emphasize the power and authority of the rulers of Slavic nations, drawing a parallel to the powerful Roman emperors. It became a symbol of absolute power and autocracy, especially in Russia.