Frederick I "Barbarossa"
Frederick "Barbarossa" (Italian for "redbeard") was a duke of Swabia, a German King, and Holy Roman Emperor. He spent much of his reign engaged in a long struggle with Pope Alexander III, who sought to establish the papacy independently from the empire and excommunicated Frederick.
The emperor attempted to establish the German states as preeminent in Europe and fought in ongoing wars with northern Italy. He drowned on the Third Crusade while trying to cross the Saleph River.
On the Web
Catholic Encyclopedia: Frederick I
Thorough biography by F. Kampers.
Third Crusade: Frederick Barbarossa
Concise overview of the Frederick and his participation in the Third Crusade by Dr. E. L. Knox at Boise State University.
Peace of the Land Established by Frederick Barbarossa Between 1152 and 1157 A.D.
Document issued by Frederick I, provided online at the Yale Law School Avalon Project.
A multi-page index of sites covering Early Europe, the Carolingian Empire, general history of the continent, and various topics in European history.