King Henry IV at Canossa in 1077 where he went in order to obtain the revocation of the excommunication imposed on him by Pope Gregory VII. According to contemporary sources, he stood for three days and three nights before the entrance gate of the castle, while a blizzard raged. Henry IV, 1050 - 1106. King of the Germans and Holy Roman Emperor. From Ward and Lock's Illustrated History of the World, published c.1882.