The museum was established on the 10th of July 1991 and opened for visitors in December 1991. It integrates the history of two successive monuments - Cotroceni Monastery and the Royal Palace. Cotroceni Monastery, built by Șerban Cantacuzino (1678 - 1688), was demolished in 1984. Cotroceni Palace was meant to represent the residence of the Crown Prince and Princess of the Kingdom of Romania, Ferdinand and Mary. Here took place crucial political events of Romania: the Crown Council (14/17 August 1916) that decided Romania's participation in World War I; in December 1918 here were received the delegates from Transylvania, Bukovina and Bessarabia who voiced their willingness to unite with Romania; in May 1918 here was signed the peace of Buftea-Bucharest; the Crown Council took place here in September 1939; Romanian and foreign personalities were received here. Cotroceni Palace was built between 1893 and 1895 by French architect Paul Gottreau. The palace was extended in the 20th century more times - mostly from 1900 to 1910 and from 1915 to 1925; in order to meet the demands of Queen Mary, several interiors were changed by architect Grigore Cerchez, who used the Neo-Romanian style. Between 1971 and 1986, the palace underwent a vast restoration, as large spaces were restored according to witnesses from the beginning of the century, while other interiors were refurbished following the pattern of the European princely residences from the 19th century. It all resulted in a variety of styles of the interior decoration. The most representative rooms are: the Hall of Honour, the Great Reception Salon, the apartment in a German Neo-Renaissance style, as well as the Henry II, Louis Quinze, Louis Seize, Rococo, Empire, Biedermeier and Art Nouveau apartments.
The exhibits include Brancovan and post-Brancovan decorative art items in a mediaeval environment: the kitchen, the refectory, cells, the princely cellars (the 17th century), the church door frame. One can see the princely residence of Cotroceni comprising original items: furniture belonging to the royal family, interior textiles, paintings. At the same time, one can see tomb stones of the Cantacuzino family, ornaments, funerary objects, coins, Smaranda Cantacuzino's costume. The museum also includes an important book collection.
The museum owns goods listed in the National Cultural Heritage Treasure.
