The Holy Roman Empire ruled over much of western and central Europe from the 9th century to the 19th century. It envisioned itself as a dominion for Christendom continuing in the tradition of the ancient Roman Empire and was characterized by strong papal authority. The greatest of these, Frederick I Barbarossa, added the word holy to the name of his empire to balance the claims of the Holy Church. He emphasized continuity with the past, going back to the days of Charlemagne.