https://www.britannica.com/topic/political-correctness
The term first appeared in Marxist-Leninist vocabulary following the Russian Revolution of 1917. At that time it was used to describe adherence to the policies and principles of the Communist Party of the Soviet Union (that is, the party line).
I remember political correctness being a hot topic in the 90s, and lately I've been wondering if that was an organic phenomenon or more of a top-down push a la the TQ nightmare of today. I still don't have an answer but the question did lead me to this fun fact that I'm sharing here.