It seemed to be strategically less important to them than for example Sevastopol. Also if I recall correctly, it was offered once to Lithuania, but turned down (due to the mainly Russian population). Russia was also in quite a weak position during the dissolution, so how did they manage to hang onto it, as they didn't really push for Crimea either.

So what was the story behind its occupation? was there more plans to get rid of it and to whom (Poland, Lithuania, even DDR)?