Frederick II, Holy Roman Emperor
Frederick II (December 26, 1194 – December 13, 1250), of the Hohenstaufen dynasty, was a pretender to the title of King of the Romans from 1212 and unopposed holder of that monarchy from 1215. As such, he was King of Germany, and of Italy, and of Burgundy. He was Holy Roman Emperor from his papal coronation in 1220 until his death. His original title was King of Sicily, which he held as Frederick I from 1198 to death. His other royal titles, accrued for a brief period of his life, were King of Cyprus and Jerusalem by virtue of marriage and his connection with the Crusades.
He was raised and lived most of his life in Sicily, his mother, Constance, being the daughter of Roger II of Sicily. His empire was frequently at war with the Papal States, so it is unsurprising that he was excommunicated twice and often vilified in chronicles of the time. Pope Gregory IX went so far as to call him the Antichrist. After his death the idea of his second coming where he would rule a 1000-year reich took hold, possibly in part because of this.
He was known in his own time as Stupor mundi ("wonder of the world"), and was said to speak nine languages and be literate in seven [Armstrong 2001, p. 415] (at a time when some monarchs and nobles were not literate at all). Frederick was a very modern ruler for his times, being a patron of science and the arts.
He was patron of the Sicilian School of poetry. His royal court in Palermo, from around 1220 to his death, saw the first use of a literary form of an Italo-Romance language, Sicilian. The poetry that emanated from the school predates the use of the Tuscan idiom as the preferred language of the Italian peninsula by at least a century. The school and its poetry were well known to Dante and his peers and had a significant influence on the literary form of what was eventually to become the modern Italian.