The end of the 11th century and the start of the 12th were marked by the Investiture Controversy. That turned on whether or not secular rulers had the right to appoint clergymen to senior positions such as bishoprics. In 1076, as part of this quarrel, Pope Gregory VII excommunicated Henry IV, Holy Roman Emperor. The Emperor crossed the Alps by way of the Great St Bernard Pass to seek out the Pope at Canossa, where in January 1077 he did public penance and had his sentence of excommunication lifted. He was accompanied by Burkhard von Oltigen, Bishop of Lausanne, who too had been excommunicated. On his return, Henry gave the region of Lavaux (which includes Glérolles) to the Diocese of Lausanne.