At the breakup of the old USSR, every eastern Europe breakaway client state wanted complete freedom fom Russian domination.
The Slavik countries, were perhaps the most insistent. When Putin seized power in Russia..one of his early moves was to break agreements, and invade the independent state of Georgia.
In any case here is the timeline of relations between Russia and the Ukraine.
https://www.npr.org/2022/02/12/1080205477/history-ukraine-russia One salient point, when th ebreakup ofth eold USSR took place, many of the old uSSR's nuclear weapons were inthe Ukraine. At thattime, Ukraine was the 3rd largest nuclear power.
In 1991, the Ukrainians held a referendum, and 92% voted for a clean break from Russia and it's influence.
The new Russia..the one now led by Putin, wanted those weapons back, and the Ukraine wanted Russia to butt out of the Ukraine's business.
So, in 1994, Pres Clinton organized "The Budapest Memorandum"wherein Russia got their nukes back and Russia promised ..no invasion, no messing in Ukrainian government issues.
Ukraine signed on, and Russia..the same Russia Putin now commands, also signed..
Atbthat time, our president promised that we would come to the Ukraine's aid if the Budapest agreement was violated..
https://www.npr.org/2022/02/12/1080205477/history-ukraine-russia A good lesson there..be careful who we elect for president...and no president should make promises, if they don't intend to keep them!
After the new Russia in the early 1990's signed off onthe breakaway republics, Putin started attacking them one-by-one. Georgia, Kazakhstan, then the Crimea...
Since Putin seized power, there have been wide spread poisonings across Europe.. of politicals who
are opposed to Putin, to include the one who led the "orange revolution", opposing Putin's hand picked candidate for Ukraine president.
https://www.atlanticcouncil.org/blogs/ukrainealert/putin-the-poisoner/ Does historic King Herod Antipas come to mind ?