Adolf Hitler was an evil son of a bitch but he's to be respected...he convinced a whole nation to go to war and come to capture in a fantastic military campaign almost the whole of Europe...that takes alot of inspiration I say...I'm no nazi and I'm not defending for him...he played he lost and he ended up in ashes his world brought down to rubble....

So I'd have to say Jack the Ripper...cuz if being evil is a sickness..he had it...he had it bad...

Also I dunno who Harold Shipman is...if he's some weirdo serial killer muthafucka...I'd have to say him,too