The pope and the king first collided over the appointment of the archbishop of
Milan. Gregory disputed Henry’s right to “invest” the archbishop (i.e., put him into
his office). In the investiture ritual, the emperor or his representative symbolically
gave the church and the land that went with it to the bishop or archbishop chosen for
the job. In the case of Milan, two rival candidates for archiepiscopal office (one
supported by the pope, the other by the emperor) had been at loggerheads for several
years when, in 1075, Henry invested his own candidate. Gregory immediately called
on Henry to “give more respectful attention to the master of the Church,” namely
Peter and his living representative—Gregory himself.^5 In reply, Henry and the
German bishops called on Gregory, that “false monk,” to resign. This was the
beginning of what historians delicately call the “Investiture Conflict” or “Investiture
Controversy.” In fact it was war. In February 1076, Gregory called a synod that both
excommunicated Henry and suspended him from office:
I deprive King Henry [IV], son of the emperor Henry [III], who has
rebelled against [God’s] Church with unheard-of audacity, of the
government over the whole kingdom of Germany and Italy, and I release
all Christian men from the allegiance which they have sworn or may
swear to him, and I forbid anyone to serve him as king.^6
The last part of this decree gave it real punch: anyone in Henry’s kingdom could
rebel against him. The German “princes”—the aristocrats—seized the moment and
threatened to elect another king. They were motivated partly by religious sentiments
—many had established links with the papacy through their support of reformed
monasteries—and partly by political opportunism, as they had chafed under strong
German kings who had tried to keep their power in check. Some bishops, too, joined
with Gregory’s supporters, a major blow to Henry, who needed the troops that they
supplied.
Attacked from all sides, Henry traveled in the winter of 1077 to intercept
Gregory, barricaded in a fortress at Canossa, high in the Apennine Mountains (see
Map 5.3). It was a refuge provided by the staunchest of papal supporters, Countess
Matilda of Tuscany. In an astute and dramatic gesture, the king stood outside the
castle (in cold and snow) for three days, barefoot, as a penitent. Gregory was forced,
as a pastor, to lift his excommunication and to receive Henry back into the church,
precisely as Henry intended. For his part, the pope had the satisfaction of seeing the
