It has already been established that Catherine the Great annexed Crimea from the Ottomans. What is the point you are attempting to make? Are you suggesting that the long gone "Ottoman Empire" be revived and that Russia should give Crimea back to the Ottomans? Crimeans, whether ethnically Tatar, Russian or Ukrainian have made quite clear that they regard themselves as Russian. They don't need or want annexing. What happens to the approx 2.5 million inhabitants of Crimea who would no longer be welcome if Ukraine were to annex Crimea?
It is obvious that your posts are inspired by your indoctrinated hatred of all things Russian rather than any coherent understanding. It is also noticeable that you simply dispute Russian sovereignty of Crimea rather than put forward a case for Ukrainian sovereignty. The Tatars, the Ottomans... In other words, Steve, you fail to put forward any positive case whatsoever for Ukrainian ownership of Crimea. This is because there is no arguable case for Crimea to be annexed against the will of its inhabitants by Ukraine. You know this but your bias prevents you from acknowledging such uncomfortable truths.
Given your "concern" over historical land acquirement, you should do USA, Canada, Australia next. The native populations of those territories were ethnically cleansed and genocided in order to annex their land. Way more brutal than anything that has happened in Crimea. Should we give back Australia to the Aborigines? How about Canada? Both are part of the UK commonwealth. I imagine you must be furious about the long standing historical grievances of the indigenous populations of those territories and spitting feathers at the treatment of the Chagossians.
There are many more cases of dubiously acquired territories that escape your analysis. Why is this? Is it because the vast majority of annexed and occupied territory in the world was done by, or with the support of, UK/US Western imperialists? You aren't on the side of the anti-Imperialists, Steve, so the clothes don't fit when you attempt to clothe yourself as one. Your concern for Crimea is transparently anti Russian and anti the will of Crimeans. You support the annexation of Crimea on behalf of Imperialists but pretend it is on behalf of "freedom" or some such. You need to ask yourself, "For whom exactly are you advocating? You full well understand that Crimeans are happy as they are and any attempt to take Crimea from Russia would lead to quite probable World War. And you don't even know for whom you want to "liberate" Crimea!