As century old stuff goes, quite a few people are aware of this IME. Then again, between the northeastern US with its very large Jewish population and Poland, perhaps I'm not dealing with a representative sample.

There were strict laws defining the rural areas of the empire where Jews were allowed to live. Only highly professional Jews were allowed to live in the capital and big centers of the empire.

The Pale of Settlement as it was called was basically the areas that had been part of the Polish-Lithuanian Commonwealth before the First Partition in 1772, plus New Russia, i.e. Odessa and its hinterland. In modern terms that's the eastern half of present day Poland, present day Lithuania, present day Belarus, a little bit of Latvia, and the western half of Ukraine - pretty much everything west of the Dnieper. Within that area Jews could live in cities, and there was massive migration from the shtetls to the big cities of the region (Warsaw, Lodz, and Odessa) Before the 1772 there were no Jews in Russia.

There were also other legal restrictions, as tsarist Russia never got around to granting Jews equal rights, something which other European countries did over the course of the nineteenth century. Russia also had massive pogroms over the last few decades of Tsarist rule, often instigated by the government. The Jewish response was mass emigration and political discontent of various ideological brands - Bolshevism, Menshevism, Polish Marxist nationalism, Jewish Marxist nationalism (Bund), Zionism (which was also sometimes Marxist), plus an attempt by many to stay within the traditional religiously governed world and pretent outside society and the modern world didn't exist.

The Communists came in promising a Brave New World in which all men were created equal. Little did people in multicultural Russia realize in those days that the strong medicine of the new regime was apt to kill the patient.

The twenties were the high point of promoting cultural national autonomy. With the advent of full fledged Stalinism there was a bloody crackdown. Things got better in the post-Stalinist era, but never reached the level of the twenties.