As the golden horse on the roof above the main entrance implies, Mainz State Museum is located in the former stables of the Electorate of Mainz built during the Baroque period. Only the outer walls of the large riding school, stables and staff dwellings survived the Second World War. In the state-of-the art museum featuring modern technology, visitors can paintings, sculptures, furniture and porcelain from the 17th and 18th centuries from Germany, France, the Netherlands and Italy.
After the destruction of the city during the Thirty Years' War and again during the War of the League of Augsburg (1689–1697), Mainz entered its golden century, and became an important centre of crafts, architecture, the fine arts and scientific learning. When the city was once more devastated in 1793, the Electorate, members of the nobility and rich canons managed to flee before the French Revolutionary Army, taking with them their most precious possessions. The invaders destroyed many churches and monasteries, and the palaces of rich burghers and merchants were taken over by the new administration of the proclaimed Republic of Mainz.
In 1803 and 1805, a total of 33 paintings were brought from Paris to Mainz (which at the time had become part of France and was known as Mayence) in order to establish a public arts museum. Among these works were a number of important Italian, Flemish and French paintings of the 17th and 18th centuries. During the 1800s, this collection grew significantly, mainly through donations by local collectors of Old Masters. In the 20th century, the museum made many acquisitions in order to complete its collection of works from the Rococo period. After the Second World War, luxury furniture from the renowned Mainz guild of carpenters known as the "Mainzer Cartourgen" that had previously been sold to collectors all over the world was eventually returned to Mainz, its place of origin. The museum also owns many single figurines as well as an entire Chinese Imperial court in porcelain produced by the Höchst factory sponsored by the Elector of Mainz. These items are displayed together with portraits by court painters, and paintings by Giandomenico Tiepolo, Jean Marc Nattier and Johann Heinrich Tischbein. The 60 maquettes by Johann Sebastian Barnabas Pfaff give a good impression of the work of one of the great sculptures from the period of transition from Baroque to Classicism. Life-size wood and stone statues of saints in timber stand opposite paintings of saints by Jakob Jordaens and Guercino, and Arcadian landscapes by Claude Lorrain.