Ah yes, the most brutal were eastern European, Ukrainian, Polish and Baltic colonies
(Not denying colonialism was and is a fucking disease, just think it's unfair to judge ALL of Europe for it when it is basically exclusively western Europe that did that shit)
Well, I mean Slovakia didn't exactly exist as a nation during the majority colonial expansion. They were part of the austro-hungarian empire, which did participate in some colonialism, though less than most at the time.