The Augustinian priory here was founded in 1080, on land donated by the Alquier noble family of Béziers. A new church was consecrated in 1115. Numerous relics were collected by the abbey and it served as cemetery to the nobility of the region. The lands owned by the priory extended to 75 villages. Pope Innocent III in the context of the crusade against the Cathars exempted the priory from control by the bishops of Béziers, making it subject only to the Holy See in spiritual matters. In secular terms, the abbey pledged allegiance to Louis IX of France in 1268.
In the 14th century the priory began to decline, as a result of the Black Plague and the turmoils of the Hundred Year's War, and the number of monks halved, from 80 in the 13th century to 40 by 1384. The monastery was pillaged during the wars of religion, in 1539, and again in 1563. By 1605, the monastic community was moribund, reduced to seven or eight monks. In 1671, it was attached to Sainte-Geneviève abbey in Paris.
The medieval buildings were torn down and the estate was rebuilt from ground in the mid-18th century under prior Pas de Beaulieu, except for the church building, which was modified but retains its 12th century romanesque core structure. After the French revolution, the monastery was dissolved and the property nationalised, in 1791 sold to an advocate, Marc Antoine Thomas Mérigeaux, who bought it on behalf of a Prince de Conti who offered it to his mistress, Madame de Brimont.
From this point, the former monastery became known as Château de Cassan or Cassan castle. It changed hands several times during the 19th and 20th centuries, eventually passing to the French state, housing administrative offices, but in 1995 sold again to a private party, and in 2002 to a real estate holding.References:
The Palazzo Colonna is a palatial block of buildings built in part over ruins of an old Roman Serapeum, and has belonged to the prestigious Colonna family for over twenty generations.
The first part of the palace dates from the 13th century, and tradition holds that the building hosted Dante in his visit to Rome. The first documentary mention notes that the property hosted Cardinal Giovanni and Giacomo Colonna in the 13th century. It was also home to Cardinal Oddone Colonna before he ascended to the papacy as Martin V (1417–1431).
With his passing, the palace was sacked during feuds, and the main property passed into the hands of the Della Rovere family. It returned to the Colonna family when Marcantonio I Colonna married Lucrezia Gara Franciotti Della Rovere, the niece of pope Julius II. The Colonna"s alliance to the Habsburg power, likely protected the palace from looting during the Sack of Rome (1527).
Starting with Filippo Colonna (1578–1639) many changes have refurbished and create a unitary complex around a central garden. Architects including Girolamo Rainaldi and Paolo Marucelli labored on specific projects. Only in the 17th and 18th centuries were the main facades completed. Much of this design was completed by Antonio del Grande (including the grand gallery), and Girolamo Fontana (decoration of gallery). In the 18th century, the long low facade designed by Nicola Michetti with later additions by Paolo Posi with taller corner blocks (facing Piazza Apostoli) was constructed recalls earlier structures resembling a fortification.
The main gallery (completed 1703) and the masterful Colonna art collection was acquired after 1650 by both the cardinal Girolamo I Colonna and his nephew the Connestabile Lorenzo Onofrio Colonna and includes works by Lorenzo Monaco, Domenico Ghirlandaio, Palma the Elder, Salviati, Bronzino, Tintoretto, Pietro da Cortona, Annibale Carracci (painting of The Beaneater), Guercino, Francesco Albani, Muziano and Guido Reni. Ceiling frescoes by Filippo Gherardi, Giovanni Coli, Sebastiano Ricci, and Giuseppe Bartolomeo Chiari celebrate the role of Marcantonio II Colonna in the battle of Lepanto (1571). The gallery is open to the public on Saturday mornings.
The older wing of the complex known as the Princess Isabelle"s apartments, but once housing Martin V"s library and palace, contains frescoes by Pinturicchio, Antonio Tempesta, Crescenzio Onofri, Giacinto Gimignani, and Carlo Cesi. It contains a collection of landscapes and genre scenes by painters like Gaspard Dughet, Caspar Van Wittel (Vanvitelli), and Jan Brueghel the Elder.
Along with the possessions of the Doria-Pamphilij and Pallavacini-Rospigliosi families, this is one of the largest private art collections in Rome.