Frederick II, Holy Roman Emperor
Overview
Frederick II was one of the most powerful Holy Roman Emperor
Holy Roman Emperor
The Holy Roman Emperor is a term used by historians to denote a medieval ruler who, as German King, had also received the title of "Emperor of the Romans" from the Pope...

s of the Middle Ages and head of the House of Hohenstaufen. His political and cultural ambitions, based in Sicily and stretching through Italy to Germany, and even to Jerusalem, were enormous. However, his enemies, especially the popes, prevailed, and his dynasty collapsed soon after his death. Historians have searched for superlatives to describe him, as in the case of Professor Detwiler, who wrote:
Viewing himself as a direct successor to the Roman Emperors of Antiquity, he was Emperor of the Romans
Holy Roman Emperor
The Holy Roman Emperor is a term used by historians to denote a medieval ruler who, as German King, had also received the title of "Emperor of the Romans" from the Pope...

 from his papal coronation in 1220 until his death; he was also a claimant to the title of King of the Romans
King of the Romans
King of the Romans was the title used by the ruler of the Holy Roman Empire following his election to the office by the princes of the Kingdom of Germany...

 from 1212 and unopposed holder of that monarchy from 1215.
Timeline

1227    Frederick II, Holy Roman Emperor, is excommunicated by Pope Gregory IX for his failure to participate in the Crusades.

1229    The Sixth Crusade: Frederick II, Holy Roman Emperor signs a ten-year truce with al-Kamil, regaining Jerusalem, Nazareth, and Bethlehem with neither military engagements nor support from the papacy.

1229    Frederick II, Holy Roman Emperor declares himself King of Jerusalem during the Sixth Crusade.

 
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