The landgraves of Kassel did not only realise ambitious construction projects. As the Gemäldegalerie Alte Meister in Schloss Wilhelmshöhe palace shows, they were also passionate art collectors. The permanent exhibition consists of around 500 paintings displayed over three floors. With 2,300 paintings in total, the collection is one of the most important of its kind in Germany.

The Old Masters are the European painters of the 14th to the 18th century. With twelve paintings by their most famous representative, Rembrandt, the Gemäldegalerie Alte Meister in Kassel houses one of the world's largest Rembrandt collections. Two of Rembrandt's best-known works are on display here: "Jacob Blessing the Sons of Joseph", and his portrait of Saskia van Uylenburgh – the artist's wife and great love.

The world-famous collection also includes numerous masterpieces by some of Rembrandt's Flemish contemporaries, such as Rubens or van Dyck The German, Italian, French and Spanish Old Masters are also represented, with major works by Dürer, Titian and Murillo.

The impressive extent of the collection is primarily due to the fact that Landgrave William the Eighth was a passionate collector. In the mid-18th century, he purchased hundreds of works of art all over Europe, and had a gallery built especially for this collection. In 1877, the paintings were moved to the building that is now known as the Neue Galerie, where they remained until the Second World War broke out. The Old Masters Picture Gallery was relocated to Schloss Wilhelmshöhe palace in 1974.