I'll admit to not knowing my history well at this point, but wasn't mathematics and the sciences rather important to socialist countries? Now I don't doubt that ideology will have been injected in certain instances, but at least in mathematics and physics that's a bit harder to do and hence there were quite a number of accomplished mathematicians in the USSR.

Even beyond the natural sciences, this seems to have been somewhat the case. I remember my uncle, who is as unabashedly anti-communist as it gets, once showing me a grammar of some minority language written in the GDR and commenting, almost with admiration, that "back then, they invested a lot of resources on things like that".