Well, I'm certainly no scholar in the lore area, but what I've gleaned from sourcebooks, the wiki and general osmosis is that the Rule of Man was plenty fascist/totalitarian/xenophobic/insert-bad-thing-here. And that was just after contact with the Ziru Sirka! And at least the Terran material in Mongoose stuff is that the Solomani Party is pretty much the stand-in for Nazis in the setting.

How wrong am I?