The moment
Benedict of Nursia settled on Monte Cassino around 529 and wrote a Rule for monks: a prologue and 73 chapters on prayer at fixed hours, work, reading, food, sleep and the authority of the abbot. Nearly all we know of him comes from Pope Gregory the Great's Dialogues. Cluny in 910 and the Cistercians after it were founded to live by the Rule, which became the standard rule of Western monasticism.
People: Benedict of Nursia, Scholastica, Gregory the Great, Hildegard of Bingen