October 20, 751: Pepin the Short, son of Frankish hero Charles Martel and father of Charlemagne, deposes the last of the Merovingian kings and becomes the first king of the Carolingian dynasty. He was crowned by Pope Stephen II, who later asked for his help when threatened by Lombards of northern Italy. Pepin defeated the Lombards, then ceded the territory he captured back to the pope, laying the foundation for the papal states.
October 20, 1349: Pope Clement VI condemns self-flagellation, speaking out against a veritable flagellation frenzy. The practice, first taught by the Benedictine monk Peter Damian in the mid-eleventh century, gained popularity during the thirteenth-century Black Death scare and continues today in isolated incidents.