foundation · 910 · Cluny Abbey
In 910 William the Pious founded Cluny with a charter unheard of: the abbey would answer to no bishop or lord, only to Peter's see. Under its great abbots the Cluniac reform disciplined western monasticism and bred the reforming papacy — the church Humbert served in 1054 was Cluny's church.
Monastic reform answerable to Rome alone — the engine of the western church's renewal.