San Salvador de Oña monastery was founded by Sancho García, the Count of Castile, for his daughter Tigridia, as a double monastery in 1011. The nuns came from the Monastery of San Juan in Cillaperlata, while the monks were from the Monastery of San Salvador in Loberuela.
In October 1033, King Sancho III of Navarre gave the monastery to the Abbey of Cluny, by which it became a part of the largest monastic organization of the era. It flourished during this period, coming to have over 70 other monasteries and churches under its authority.
In 1506 the monastery joined the Benedictine Congregation of Valladolid, which had a program of a return to the reformation of the monastic life, following a strict interpretation of the Rule of Saint Benedict. It was badly damaged during the Peninsular War of the Napoleonic era, and the monks were dispersed.
In 1835, the monastic church was converted into a parish church to serve the people of the town. The property of the monastery was returned to the Catholic Church in 1880, when it was acquired by the Society of Jesus. They occupied the buildings for nearly 90 years.
The monastic complex came into the possession of the Province of Burgos in 1968, at which time it was used as a psychiatric hospital.
The surviving architecture of the monastic complex is a series of connected buildings, ranging in date from the Romanesque style of the 12th century, commonly seen in Cluniac monasteries, to the Gothic renovations of the 15th century.
The gate to the monastery is a notable example of the Mudéjar style.
The interior of the monastery church measures 83 meters by 20 meters, with a height of 20 meters. It was renovated in the 15th century and contains a number of paintings attributed to a monk of the community, Dom Alonso of Zamora.
In the sanctuary can be seen a Renaissance-era altarpiece of the Immaculate Conception, along with remains from the medieval altarpiece it replaced in the 15th century. The choir has a domed vault built about 1460 by Fernando Díaz. An apse was opened in it during the 18th century to house the relics of St. Íñigo of Oña (died 1057), one of the first abbots of the monastery. The choir stalls there, also from that period, were carved in walnut by Dom Pedro of Valladolid.
The Monastery of San Salvador became the final resting place for many of the leading figures of northern Spain, especially during its early centuries of operation.
References:Saint-Georges de Boscherville Abbey is a former Benedictine abbey. It was founded in about 1113 by Guillaume de Tancarville on the site of an earlier establishment of secular canons and settled by monks from the Abbey of Saint-Evroul. The abbey church made of Caumont stone was erected from 1113 to 1140. The Norman builders aimed to have very well-lit naves and they did this by means of tall, large windows, initially made possible by a wooden ceiling, which prevented uplift, although this was replaced by a Gothic vault in the 13th century. The chapter room was built after the abbey church and dates from the last quarter of the 12th century.
The arrival of the Maurist monks in 1659, after the disasters of the Wars of Religion, helped to get the abbey back on a firmer spiritual, architectural and economic footing. They erected a large monastic building one wing of which fitted tightly around the chapter house (which was otherwise left as it was).