Places in Russia tend to change their names with the tides of history. St. Petersburg was founded by Peter the Great in 1703 and was known as such until 1914, when Nicholas II changed its Germanic sound to Petrograd, “Peter’s city.” In 1924, the Bolsheviks renamed it Leningrad. In 1991 it became St. Petersburg once again. Tiflis is now known as Tbilisi, the capital of independent Georgia.
The rulers of Russia were called Tsars, though in 1721 Peter the Great declared himself Emperor and thenceforth the Romanovs were known as both.
Russians use three names in a formal context: a first name, a patronymic (meaning son/daughter of) and a surname. Thus Sashenka’s formal name is Alexandra Samuilovna Zeitlin and Vanya’s is Ivan Nikolaievich Palitsyn. But Russians (and Georgians) usually also use diminutives as nicknames: Sashenka is the diminutive of Alexandra and Vanya is the diminutive of Ivan, etc.
In the Pale of Settlement, the Jews spoke Yiddish as their vernacular, prayed in Hebrew and petitioned in Russian. The Georgian language is totally different from Russian and has its own alphabet and literature.