Frederick II, nicknames "Stupor Mundi" (The World's Wonder) was King of Sicily from 1198, king of Germany from 1212, King of Italy and Holy Roman Emperor from 1220 and King of Jerusalem from 1225. His political and cultural ambitions were enormous as he ruled a vast area beginning with Sicily and stretching through Italy all the way north to Germany. As the Crusades progressed, he acquired control of Jerusalem and styled himself its king.—Ulf Kjell Gür