It was not nominal at the beginning. All these countries fell off during revolution, granting them some autonomy was necessary to bring them back.
Ideology wasn't about Russian culture, it was about universal 'communist' culture. People who didn't fit into that were persecuted regardless of their nationality. Russian language was promoted simply because it was already most common language.
P.s. You do remember Stalin was Georgian, right?
Those countries were brought back by arms, not by feint promises of autonomy. The Bolsheviks fought for every bit of land wanting to secede from the Russian Empire (e.g. arming and inciting a Communist rebellion in Finland). Meanwhile good ol' Lenin was publicly announcing that any nation and peoples willing to declare independence is free to do so and will not be opposed, while in practice doing the exact opposite. About half of the nations wanting independence from Russia actually managed to keep it - through arms. Others, like Ukraine and Belorussia, fell to the RKKA. Soviet Russia was federalised on paper and officially turned into the Soviet Union just to give it legitimacy. Legitimacy that only those who were naive enough would buy into.
You're right, it wasn't about Russian culture. The Russian Communists butchered their own culture. But they didn't replace it with anything universal, even if that was the intention of some idealists. Which brings me to my point: Warm and fuzzy ideologies are one thing, what's happening in real life is another. The Russians colonized places like the Baltic nations, Kazakhstan, Karelia, Crimea and to an extent the Ukraine, etc. By the late 70s countries like Latvia and Estonia were 50% Russian. Had the USSR not collapsed when it did, Estonians and Latvians would now be a minority in their own country. Kazakhstan had similar figures. In fact even today the populations of these countries are 30-40% Russian, which is a direct result of active Russification during the Soviet era.
Now these are cold hard historical facts. I don't see how the original intention (what ever it might be) of Lenin, Trotsky and the other original Bolsheviks changes what happened in practice.
Yeah, I mentioned the odd Georgian General Secretary, and also mentioned that that in itself does not mean much. Actually come think of it, your post doesn't really refute anything that I said. Maybe I shouldn't even have bothered to reply, hah.
EDIT:
well, what did you expect? this is not something that was solely a problem in the USSR, this happens almost everywhere where you have a majority population, like the US, do they oppress minorities? yes, one example is native Americans, they technically have their own nations who are governed by the US federal government, a government that has oppressed them for as long as it has existed, attempting to erase their culture and languages, and americanizing their people. Japan's erasure of the indigenous Ainu population of Hokkaido, and their colonial policies in Korea, and in WW2. this happens everywhere that there is a majority population.
and to be fair, Russian be the "lingua franca" of the USSR is not really an oppressive policy, it was simply convenient and logical, Russian was the most commonly spoken language in the USSR, Russia was the largest of the soviet republics both in terms of land, population, and economy, and Russians were the majority population
that is simply not true, monarchies are nothing more than hereditary dictatorships, many of those have been successfully democratized.
also it is worth to point out that in the "referendum on the future of the Soviet Union" in 1991, 73% of the Russian population (77.8% in total in the entire USSR) voted to keep the soviet union and it's communist system (tho with democratic reforms) also according to a survey last year 55% of Russians today miss the USSR
Not necessarily. I don't mean to brag, but Finland is a good example of very good treatment towards a sizeable minority, in this case our Swedish-speaking minority. To such an extent actually, that it isn't necessarily a good thing for the majority population. Then again we're a small country with no imperial past and therefore no inherent tendency to delusions of grandeur that involve forceful assimilation or getting rid of minorities in ways we're not allowed to talk about on these forums.
I wasn't referring the language as an oppressive policy (although come think of it, teaching only Russian in schools in native areas like Udmurtia, Mari-El etc. is oppressive), I was citing it as an example of how Russian the USSR in practice was. The oppressive part was more referring to things that we unfortunately are not allowed to talk about here.
Fair enough, you're partially right. But do consider the fact that the few constitutional monarchies that are still around, have gone through a "democratisation" process that has lasted for decades or even centuries. I can't think of a single country of any meaningful size with an absolute monarchy that rapidly devolved administrative power and still kept the monarchy as at least the nominal head of state.
In any case the point was, that you can't build something with violence and brute force, hold it together with terror, and then expect it to stay intact when you loosen the leash. The Russians may have wanted to keep the USSR (understandably so - like I said, it was a de facto Russian state), but the non-Russian people under them never wanted to be there in the first place, and they took the chance to get out as soon as it appeared.