In 1946 after the World War, elections were held in Romania and by trickery and lying the Communist party won. The USSR or Union of Soviet Socialist Republics influenced its surrounding countries such as Romania. However even the countries that were just influenced by USSR and not part of it were controlled by USSR.
What brought the USSR Down
Mikhail Gorbachev, the last president of the USSR, wanted to make the communist government transparent. He wanted to explain to the people why actions were taken, instead of imposing it on them. This required the demolition of the old political leaders in the communist countries, but when the leaders were taken down new ones couldn't be put up.