What influence did the perestroika, which began in the USSR, had on the situation in Eastern Europe?

The USSR considered Eastern Europe a strategic territory, and therefore exerted a great influence on it. The Soviets supported the communist government there by all possible means. But during perestroika, a number of revolutions took place in these countries, during which democratic forces came to power, they were loyal to Western Europe and promoted values that were completely different from those in the USSR. Thus, thanks to perestroika, the Eastern European countries were able to get rid of the influence and, in many respects, control from the USSR.