Walk to Canossa
The glory of the Empire almost collapsed in the Investiture Controversy, in which Pope Gregory VII declared a ban on King Henry IV (king 1056, Emperor 1084–1106). Although this was taken back after the 1077 Walk to Canossa, the ban had wide-reaching consequences. Meanwhile, the German dukes had elected a second king, Rudolf of Swabia, whom Henry IV could only defeat after a three-year war in 1080. The mythical roots of the Empire were permanently damaged; the German king was humiliated. Though, most importantly, the Church was clearly an independent player in the political system of the Empire, not subject to imperial authority.