Question

Where did the Soviet Union set up pro soviet regimes?

Answer 1

Initially pro-soviet regimes were set up everywhere behind the iron courtain, i.e. all countries that were occupied by the red army after WWII. That was Poland, Hungary, Czechoslovakia, East Germany, Bulgaria, Romania, Albania and Yugoslavia.

In East Asia they set up a pro-soviet regimes in North Korea and Mongolia. Later when Chinese revolution was won, China also had a pro-soviet regime.

As the cold war developed, each country was effectively a battleground of ideologies. All countries, that gained their independence from colonialism, were up for grabs, and most of them turned to where they got a better deal.