St. Odo, 878--942 A.D., was of noble birth and was educated in Paris. Around 909 he became a monk, was ordained priest, and assigned as head of the Abbey School at Baume. When, in 910 Abbot St. Berno founded a new monastery at Cluny, St. Odo accompanied him and took with him his library of 100 books, a significant number in those days. St. Berno died in 927 and was succeeded as Abbot by St. Odo. During his tenure, St. Odo instituted significant reforms and expanded the number of monasteries affiliated with Cluny, beginning what eventually became a congregation of federated monasteries spread through Europe (chiefly in France and Italy). He was noted for his good humor, musical compositions, and writings. Though himself a strict ascetic, he was known for his kindness and tolerance of others, especially the weaker brethren. Before his death, he remarked that, if he was to be condemned, he would rather it be for his leniency than for excessive severity to the brothers.
Due in large part to St. Odo's labors, the Cluniac congregation was very influential
throughout the early middle ages. At its height, in the 15th century, the congregation had 825 individual monasteries of various sizes. Cluny itself, at one time the largest church building in Christendom, functioned for a long time in a manner similar to the monasteries of the "un-sleepers," in Constantinople, where rotating teams of monks maintained constant prayers and services in the chapel around the clock. In spite of the ill effects of eventual laxity and wealth in its latter centuries, Cluny remained a functioning Benedictine monastery until it was closed and demolished during the French Revolution, by the end of which, monasticism had been eradicated throughout France. It was not revived until 1833, when the Abbe Prosper Gueranger and four other priests moved into the former priory of St. Pierre de Solesmes.