9th century. The territory was conquered by the Moorish invasion in the year 716 and was later won back and repopulated in the course of the creation of Carolingian Catalonia.

c. 900. The Church of Santa Cecilia de Montserrat is mentioned for the first time located near pre-Roman Castle Marro. No trace of this castle remains. Its function was probably that of a defensive watchtower for the church and the whole valley of Marganell, the nearest village.

942. The priest Cesari bought Castle Marro and the Church of Santa Cecilia for 10 ounces from his aunt Druda and cousin Ansulf.

945. On June 24, Bishop Jordi of Vic signed the foundation certificate for the Benedictine Monastery of Santa Cecilia de Montserrat. It was ruled by Abbot Cesari with the consent of Count Sunyer and Countess Riquilda of Barcelona. Riquilda was a great advocate of Cesari and his monastery.

957. Bishop Guadamir of Vic consecrates the Church of Santa Cecilia de Montserrat. The church had been restored by Abbot Cesari, and housed three altars dedicated to Saint Mary, Saint Cecilia and Saint Peter.