Frederick II (1090 - 6 April 1147), called the One-Eyed, was duke of Swabia. He was the eldest son of Frederick I, Duke of Swabia, and Agnes of Germany. He succeeded his father in 1105. In 1121 he married Judith of Bavaria, a member of the powerful House of Guelph. On the death of Emperor Henry V, his uncle, Frederick stood for election as King of the Romans with the support of his younger brother Conrad, duke of Franconia and several houses. Wikipedia
The definitive Wikipedia entry for Frederick II, Duke of Swabia. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Frederick_II,_Duke_of_Swabia
The definitive Wikipedia entry for Frederick II, Duke of Swabia. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Frederick_II%2c_Duke_of_Swabia