what are some ways to categorize the countries of the former soviet union into 4 or 5 groups?

Answer 1

First: The Baltic states of Estonia, Latvia, and Lithuania, which were absorbed into the Soviet Union in 1940. Second: The satellite states of Poland, Czechoslovakia, Bulgaria, Yugoslavia, Romania. Third: States that were originally SSR's, like Belarus, Kazakhstan, Uzbekhistan, Tadjikhistan, Turkmenistan, and the Buryat Mongol Autonomous Region.