It was a creation of the Soviet Union. Some of it was part of Russia since the time of Catherine the Great. Some of it they stole from Poland. It was never an independent country with its present borders.
A lot of it did not even exist in 1922 sine it was still part of Poland then. So it certainly wasn't part of the Soviet created Ukraine "Republic"
And it wasn’t sovereign Russian territory in 1992.
But what’s your point? That historical precedence justifies present day aggression? Do you agree with Aztlan that the American Southwest should return to Mexico? Would you support a Mexican invasion of Texas?