December 26th is the birthday of Frederick II, who lived from 1194 to 1250 and was at various points the Holy Roman Emperor, a German King, King of Sicily, and King of Jerusalem, because when you're Holy Roman Emperor you can just do that.
He has been called one of the most arresting figures of the middle ages. In fact, on one particular day he sent 168 of his own guards to central booking for possession of a controlled substance. A few hours later he called the jail and said "just kidding you guys!" and they all laughed at what a funny joke that was.
Frederick called himself "lord of the world," and everyone around him was too scared to say just calling yourself that is kind of meaningless. People had strong feelings about him. Some contemporaries called him stupor mundi, which either means "wonder of the world" or "stupid mundi." Others hated him and called him the anti-christ, to which he would respond "if I were the antichrist, would I be able to do THIS?" And then he'd pull his cloak up and turn around three times making a lot of swooshing noises, and everyone had to pretend they believed he'd disappeared. He was sensitive about his skills at magic, specifically the art of illusion.
His personality and style of leadership were a curious mix, and some critics thought him contradictory. For instance, he was Christian, but he had a harem--"because I'm the goddamn emperor of the universe practically, that's why." He frequently clashed with the Pope, yet he also persecuted heretics. This was just to keep everyone on their toes. Though interested in art and poetry--he wrote many poems and even wrote a book on bird anatomy--he was known to be quite cruel. He famously told one artist, "Sir, is this a painting, or did your pallet just throw up?" and then he chopped his head off.
Conflicts between Frederick and the pope led to the complete destruction of the house of Hohenstaufen. The roof collapsed and several chairs turned quite moldy.