putting my hand on the lathe In Dune Messiah, they're going to replace the part where Paul compares himself with Hitler, and have him quote the victims of communism propaganda.
he's not russian, he's just vaguely russian-coded to sound evil. he is evil, yes, but also herbert felt like painting him russian for reasons... he failed a bit because harkonnen was taken from a finnish surname afaik.
The origin of the name Harkonnen is Härkönen, a Finnish name. Herbert apparently saw that name in a phone book and thought it sounded Soviet. As always, libs do no research and just assume whatever the fuck they want.