1088:

Pope Urban II elected

Urban continued the ecclesiastical reforms begun by his predecessor Gregory VII and strengthened the papacy as a political entity. He is perhaps best known for beginning the Crusade movement.

604:

Pope Gregory I

Saint Gregory was the foremost influence in shaping the medieval papacy, drawing on Augustine's City of God for his theological foundation. Strongly involved with monasticism, Gregory also reformed the mass, which enabled the development of Gregorian Chant.