The monastery of Oseira was founded by the Benedictines in 1137, converting to the Cistercian order a few years later. Around the year 1140, San Bernardo sent a group of monks from Claraval to indoctrinate the founders the new rule. In the XII and XIII centuries, a shrine was erected in an inaccessible location in the province of Ourense. It was built following the model of the Cathedral of Santiago with apse-aisle in the altarpiece, as well as the typology of the order, with a barrel vault central nave, without triforium and very elemental decoration with geometric capitals.

At the end of the XIIIth century, in the center of the transept, a great dome was built on lierne ribs supported on cradles, work attributed to a monk called Fernán Martínez. The chapels of the apse-aisle, underwent several reforms, only conserving the Romanesque. Around the end of the XVth century, the construction of the current capitulary room was begun, with four central fluted and twisted shafts, of which take off lierne ribs interlaced by arches in a capricious and original vault.

After a fire ruined the monastery in the XVth century, a long restoration was initiated. In 1647, the choir at the base of the shrine, the cloisters and the new baroque facade of the church with the two belfry towers were erected. The complex has three cloisters, that of the pinnacles, the medallions and the gentlemen. After the disentailment of 1835, they deteriorated into a ruinous state. The restoration of the monumental structure was begun in the 1930s and continues nowadays.
 
 

  

  

Dpto. de Composición.  Universidade da Coruña.