Europe

Hm, I once wrote a long text about the word "höhlä" in Finnish. Its existence and etymology alone tell a lot about the centuries of trying to get rid of Ukrainians.
But, there are 39 Finno-Ugric languages. You might know of Finnish, Estonian and Hungarian. And then there are 10-ish Sámi languages. But who are the rest? Why do you never hear of them? And only a part of the nations colonized by the Russia are Finno-Ugric. There are the Aleutian, there are the Altaic, there are the Turkic and there are the various Caucasian cultural groups I understand much worse than the four other groups I've mentioned. (Except that I'm currently learning Ingushetian and have learned it's very close to Ichkerian, a.k.a. "Chechnyan")

And yeah, people don't often understand the history of place names such as the name of the "Novorossijsk". That translates literally to "Newrussia-town". They named it that way because it was founded when those lands were taken from the nation that lived there previously and assimilated under the Russian culture. Those were the "New lands", or in Russian: "Novorossija". Go to Youtube and find about the Kubanskaya Balachka. Its speakers vehemently say it's not Ukrainian, but a form of Russian, but being able to speak both Ukrainian and Russian, I find the case absolutely unambiguous. But indeed: Those families who were able to say with straight face "no, we are absolutely Russians and nothing else!" were the only ones who weren't disappeared to Siberia. And that's what they say to this day. But Russians cannot understand that "dialect", while Ukrainians don't even recognize it as not being Ukrainian, unless explicitly told they are not listening to Ukrainian but Kubanskaya Balachka.
In the 1920's and 1930's USSR formed Ukrainian-language youth choirs in the area of Novorossija in the Russian Socialist Federative Soviet Republic, RSFSR. Soon after, all children that had enrolled to those choirs, plus their siblings and parents, were sent to work camps in Siberia. But Ukrainians were not really special in that regard. The Russian Empire, and later USSR, was constantly doing the same stuff to all nations within the territory controlled by it.

But, to answer this:

What is happening besides Ukraine?

Just take a look at https://en.wikipedia.org/wiki/Ethnic_groups_in_Russia . Look at the sheer number of names of nations listed there. Each of those was a full-fledged nation of its own just a bit over 100 years ago. Only the construction of the Trans-Siberian Railway truly expanded the Kremlin influence further than some 500 km from Moscow. Until that, those lands were parts of the Russian empire basically only on paper. Without a connection neither by railway or by sea, there was no sensible way of ruling those lands. The only way to move about was along "roads", that were rather paths than anything we would contemporarily call "roads". There was no infrastructure like the Swedish network of gästgiveri establishments, so the only way to get anywhere more than a day's riding trip from home was to pack your own tent and have some seriously good survival skills. And that's not something the Czars were doing. Going to some place in eastern Siberia to give orders to the locals would have been an endeavour akin to what Marco Polo did. Until the construction of the Trans-Siberian railway most of those nations were just living their life. Some maybe paid tax to Moscow, most didn't. And now they are a list of nation names feeling endlessly long, and you have almost never heard of any of them. What did your mother tell you about the Mordvins? Or the Soyot? Or the Sakha? Those tens and tens of nations have fallen into nothingness in our minds, even though in the end of 1800's they were thriving. Their disappearance is what is happening besides Ukraine. And it's an ongoing process. In Finland we keep reading news about what is happening to the rights of the Finno-Ugric nations because they are cultures similar to ours, speaking language more or (much) less similar to ours, and following traditions of our old pre-christian religion, but for central Europeans those news are of as much interest as news on some tribes in Nigeria or Ethiopia. For us it means loss of our own roots, because for us those nations are similarly close as the Spanish and Greek, French and Czech are for each other. When you more people in your own family, you understand your own nuclear family much better than you otherwise would. Of course, the Soyot and Sakha not being Finno-Ugric, we don't really read much anything about them in Finland, either. But it's easy to check that their plight is very analogous to that of the Finno-Ugric nations, so we also have an understanding of their situation.