Gregory thought that the threat of excommunication would compel rulers to abide by his move against lay investiture. Immediately, however, Henry IV in the Holy Roman Empire, William the Conqueror in England, and Philip I in France protested because the reform would deprive them not only of church income but also of the right to choose which monks and clerics would help them administer their kingdoms. The strongest reaction came from the Holy Roman Empire. Within the empire, religious and secular leaders took sides to pursue their own advantage. In January 1076, many of the German bishops who had been invested by Henry withdrew their allegiance from the pope. Gregory promptly suspended them and excommunicated Henry. The pope told German nobles they no longer owed allegiance to Henry, which obviously delighted them. When powerful nobles invited the pope to come to Germany to settle their dispute with Henry, Gregory traveled to the north. Christmas of 1076 thus witnessed an ironic situation in Germany: the clergy supported the emperor while the great nobility favored the pope.
Henry managed to outwit the pope temporarily. In January 1077, he approached the castle where the pope was staying. According to a letter later sent by Gregory to his German noble allies, Henry stood for three days in the snow, imploring the pope to lift the excommunication. Henry’s pleas for forgiveness won him public sympathy, and the pope readmitted the emperor to the Christian community. When the sentence of excommunication was lifted, Henry regained the emperorship and authority over his rebellious subjects; however, he continued his moves against papal power. In 1080, Gregory again excommunicated and deposed the emperor. In return, when Gregory died in 1085, Henry invaded Italy and captured Rome. But Henry won no lasting victory. Gregory’s successors encouraged Henry’s sons to revolt against their father.
In 1122, at a conference held at Worms, the issue was settled by compromise. Bishops were to be chosen by the clergy. But since lay rulers were permitted to be present at ecclesiastical elections and to accept or refuse homage from the new prelates, they still possessed an effective veto over ecclesiastical appointments. Papal power was enhanced, but neither side won a clear victory.
The long controversy over lay investiture had tremendous social and political consequences in Germany. The lengthy struggle between papacy and emperor allowed emerging noble dynasties to enhance their position. When the papal-