It was situated on the confines of Normandy and Brittany. The founder was Vital de Mortain, who set up a hermitage in the forest of Savigny (1105). Rudolph, lord of Fougeres, confirmed to the monastery (1112) the grants he had formerly made to Vital, and from then dates the foundation of the monastery. Tts growth was rapid, and Vital and St. Aymon were canonized. It had 33 subordinate houses, within thirty years. It continued to exist until the Revolution reduced it to a heap of ruins, and scattered its then existing members. The church was restored in 1869.