Actually, Ukraine was not "part of Russia" during the USSR era, and that is one of the main reasons there are problems now. Ukraine was a separate republic, in the USSR.

I am too fed up with the whole business to explain it though.

The USSR was a union with some similarities to the EU, but of course a closer union than the EU, and a different type of governance.
In terms of closeness between the Soviet republics, it was somewhere in between states of the USA and the nations of the EU.
Read this to understand the organisation of the USSR into Republics and Regions.

http://en.wikipedia.org/wiki/Republi...e_Soviet_Union

Autonomous Soviet Socialist Republics of the Soviet Union - Wikipedia, the free encyclopedia

This system worked well during Soviet days, as far as I understand, but it lead to several wars after the breakup of the USSR, since a number of regions had been in the "wrong" Soviet republic (which didn't matter much during Soviet days, but suddenly became important when regional languages were pushed hard in the new countries, or ethnicity/religion became a big deal.

As a result these regions subsequently ended up in the "wrong" country when the USSR split up. Examples: Nagorno Karabach, Pridnestrovie, Gaugazia, Crimea and possibly Donbass, South Ossetia, Abkhazia and probably some more places that I don't know about. Hopefully the names should sound familiar - there have been wars or conflicts in all of these places, mainly in the 1990s.

In the USSR ethnicity, religion and language had been somewhat secondary to the Soviet ideal of a strong union, and the State had prevented extreme regionalism.

The problem was: Soviet leaders had transferred regions from one Soviet republic to another for, in hindsight, unwise reasons. Of course, they envisaged the USSR would last indefinitely and did not realise what a huge problem they created with their grand gestures or administrative decisions taken in Moscow... The Donbass area was given to the Ukrainian ASSR in such a gesture, in the 1950s.

As a result it ended up in the modern nation of Ukraine, despite being historically Rusisan.

(When reading Wiki, bear in mind that a lot of the edits of these types of articiles in Wiki were traced back to US gov't agencies before it was revealed and they smartened up. Now they probably use proxies and aliases.)