One of my grandmothers, born about 100 years ago in Romania (she’s not with us anymore), told me many times she was denied from pursuing math education because of then Nazi policies of “numerus nulus” i.e. the exclusion of jews from public universities.

There’s a fascinating wikipedia page on the topic of racial academic exclusions - https://en.m.wikipedia.org/wiki/Numerus_clausus

And related to math exams, this paper of problems that looked easy but were quite difficult (and which were given to jews in the USSR) is also quite interesting — https://arxiv.org/abs/1110.1556