The humiliation of Henry at Canossa is so dramatic and so famous an event that it is hard to realise that it was but an incident in the midst of a long struggle. It settled nothing, and profited neither Henry nor Gregory. Gregory found that his harshness had to some extent alienated that public opinion on which the Papacy depended almost entirely for its influence. Henry found that his submission had not won over his German enemies, but had thoroughly disgusted the anti-papal party in northern Italy, upon which alone he could count for armed support. The Lombards now talked of deposing the cowardly monarch in favour of his little son. But the future course of events rested after all upon the action of the German nobles, who held their Diet at Forchheim in March 1077. [Sidenote: Diet of Forchheim, March 1077.] To this assembly Henry was not even invited; and for the present he preferred remaining in Italy. The Pope also did not appear in person, but was represented by two legates. The old charges against Henry were brought up once more, and the legates expressed their wonder that the patient Germans had submitted so long to be ruled by such a monster. Without giving Henry the least opportunity of refuting the accusations, it was determined to proceed at once to the choice of a new king. The suffrages of the magnates fell on Duke Rudolf of Swabia. [Sidenote: Rudolf of Swabia, Anti-Cæsar.] Before his appointment, Rudolf was compelled to renounce all hereditary claim to the throne on behalf of his heirs, and to allow freedom of election to all bishoprics. He was then crowned at Mainz by Archbishop Siegfried.
The news of Rudolf’s election at once brought Henry back over the Alps. He soon found that he now had devoted partisans in the land that had rejected him when he was under the ban of the Pope. He was warmly welcomed in Bavaria, in Burgundy, and especially in the great towns of the Rhineland, always faithful to the imperial cause. [Sidenote: Civil war between Rudolf and Henry, 1077–1080.] Rudolf’s own duchy of Swabia rejected its duke in favour of the prince who had ever loved the Swabians. Rebel Saxony was alone strongly on Rudolf’s side. Even the Pope could not make up his mind to ratify the action of his legates and accept Rudolf as king. For more than two years civil war raged between Rudolf and Henry. It was substantially a continuation of the Saxon revolt. At last, in January 1080, a decisive battle was fought at Flarchheim on the banks of the Unstrut, in which Henry was utterly defeated. [Sidenote: Battle of Flarchheim, 1080.] During all this time Gregory had contented himself with offers of arbitration. Though Henry practised lay investiture as freely as ever, it was not until after his defeat that the Pope once more declared himself against him. Yielding to the indignant remonstrances of Rudolf and the Saxons, he convoked a synod at Rome in March 1080, where he renewed Henry’s excommunication, and again deprived him of his kingdoms of Germany and Italy. [Sidenote: Renewed excommunication and deposition of Henry, March 1080.] ‘Act so,’ said Gregory to the assembled prelates, ‘that the world shall know that ye who have power to bind and to loose in heaven, can grant or withhold kingdoms, principalities, and other possessions according to each man’s merits. And if you are fit to judge in things spiritual, ought ye not to be deemed competent to judge in things temporal?’ Rudolf was now recognised as king, and another universal prohibition of lay investitures was issued.