"GUS" is the German equivalent acronym for "CIS" (Commonwealth of Independent States), i.e. the post-Soviet successor states such as Belarus, Ukraine etc.

the three powers were the United States Great Britan and The Soviet Union '-'

The way states engage with one another is called an International system. The Post War International System changed after the end of World War II. There were only two major world powers left after that war. The United States and the Soviet Union. The United States still hold power as the major world superpower since the fall of the Soviet Union.

They had experienced earlier uprisings that prepared their people for independence.

They had experienced earlier uprisings that prepared their people for independence.