we have actual mind control. only it's forbidden to use it. only not everyone cares about that. but definitely they were not mind controlled.
oh. um. we followed this voldemort person and he was all, 'kill muggleborns and muggles because they are super unworthy' and we were like, 'yeah, that sounds right'. because people in my dreams were like, 'blood purity is suuuuper important'. but whatever. death eaters. kind of mental.