The history of the Royal Castle goes back to the fourteenth century when the Great Tower was erected. In the sixteenth and seventeenth centuries during the reign of Sigismund III Vasa, the Castle underwent large-scale expansion and was transformed into a five-winged edifice with an inner courtyard. It was a royal residence, the place where parliamentary deliberations were held and the administrative and cultural centre of the country. Destroyed in the middle of the seventeenth century during the Swedish Wars, it gradually regained its former magnificence during the reign of the Saxon-Wettin dynasty. In the second half of the eigheteenth century, artists in the employ of Stanislaus Augustus (Jan Christian Kamsetzer, Marcello Bacciarelli, Domenico Merlini) reconstructed the interiors of the chambers, comprising the Great Apartment and the King's Apartment. During the period of the partitions (in the nineteenth century) the major part of the collections of the last Polish king ended up in Russia. After Poland regained its independence, some of the works of art were reinstated to their rightful place in the Castle.
In September 1939 the Castle was bombed by the Germans; however museologists, under the leadership of Professor Stanisław Lorentz, managed to salvage some elements of the interiors and also some of the works of art. In September 1944 the Castle was blown up by the Germany army. In the years 1945-1970, the Communist authorities delayed making a decision on whether to rebuild the Castle. The decision to do so was taken in 1971. Funds for the rebuilding of the Castle which took until 1980 were provided thanks to the dedication of the community.