Rasputin. And all the <100 serial killers. I mean seriously, your average Senator has signed off on more deaths than that in their first week in office.

Bundy, Dahmer, Manson, Assad, so name a few, don't seem to really rise to the level of most hated in history. Sure they're really fucked up but their impacts were relatively localized compared to the like of Nero or Wilson. Not that I think people DO hate Wilson and FDR this much. Just that they should. They don't in part because of one of the reasons they should -- commanding a massive apparatus including huge propaganda campaigns to cover for their effectively turning a free republic into a client state of London bankers.