1194 - 1250
German Emperor

Frederick II was the last of the important medieval emperors.

Frederick grew up in Sicily as his mother was the daughter of the Norman King of Sicily. The court was full of educated Arabs and Frederick got a Muslim view of Christianity as well as a Christian view of Islam.

This heretic upbringing culminated in a lifelong struggle between emperor and pope after Frederick II had secured the imperial crown. He got excommunicated by Pope Gregory IX but Frederick, unconcerned, embarked on a Crusade to win back Jerusalem from the Muslims.

On his return he reconquered Sicilian lands which had been taken by papal troops. He proposed a union of European princes against the ambition of the pope to become ruler of Europe. The emperor got excommunicated a second time and this time Frederick proposed to his fellow princes a general confication of church property.

In the end Rome defeated him, but the struggle left the prestige of the Papacy so badly shattered that Papal domination declined.

www link :

The Medieval Sourcebook:
Statute in Favor of the Princes