157th Pope of the Catholic Church. Pontificate 1073 - 1085. One of the great reforming popes, he is perhaps best known for the part he played in the Investiture Controversy, his dispute with Holy Roman Emperor Henry IV that affirmed the primacy of papal authority and the new canon law governing the election of the pope by the College of Cardinals. He was also at the forefront of developments in the relationship between the emperor and the papacy during the years before he became pope. Gregory VII was beatified by Pope Gregory XIII in 1584 and canonised in 1606 by Pope Benedict XIII as Pope St. Gregory VII.