The Investiture Controversy, also known as the lay investiture controversy, was the most important conflict between secular and religious powers in
The controversy led to many years of bitterness and nearly fifty years of civil war in
In the higher ranks of the German clergy, Gregory had many enemies. Therefore
The [excommunication] of the king made a deep impression both in Germany and Italy. Thirty years before, Henry III hadthree popes, but when Henry IV tried to copy this procedure he did not have the support of the people. The Saxons began a second rebellion, and the anti-royalist party grew in strength from month to month.
The opposition of the rebellious German nobles used the excommunication of Henry to set up a rival king
Duke Rudolph of Swabia (
This was widely felt to be an injustice. When Rudolph of Swabia died on 16 October of the same year, Henry, now more experienced, took up the struggle. In 1081 he opened the conflict against Gregory in Italy. Gregory had now become less powerful, and thirteen cardinals deserted him. Rome surrendered to the German king, and Guibert of Ravenna enthroned as
Clement III (24 March 1084). Henry was crowned emperor by his rival, while Gregory himself had to flee from Rome in the company of his Norman "vassal,"