The origin of the abbey is traditionally linked to Charlemagne, who is portrayed in a fresco fragment within the church. The 9th century edifice was rebuilt a first time from 1007 by the Benedictine monk St. Theobald. It is dedicated to St. Liberator. The current edifice, however, is that rebuilt starting from 1080 by Desiderius, abbot of Montecassino. The church remained in a decaying state until it was restored in 1967-1971.