this is completely wrong.  when the ussr was collapsing gorbachev and yeltsin quite literally said they refuse to give up parts of eastern ukraine and that borders would need to be redrawn.  this was back in the 90s, well before any "discoveries". they had to give up because of western pressure and instead made various agreements like sharing the black sea ports (which the ukrainians later reneged on). this was always going to happen because the areas in question were always russian.  this is a good place to start for anyone who wants to learn what actually happened and why, it's from 2015.   o.uk/2015/02/a-not-so-brief-history -of-crimea.html
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