In 1958, Moderna Museet opened in Stockholm. The museum collections then consisted largely of art transferred from Nationalmuseum, but also of purchases, gifts and donations intended specifically for a future Swedish modern art museum. Ten years earlier, at the end of June 1948, Prince Eugen's Waldemarsudde was inaugurated, a museum that by definition can be considered Sweden's first museum for modern and contemporary Swedish art. In his will, Prince Eugen handed over his former home with the art collections to the Swedish state with the aim of turning it into a public museum. This gave the prince's art collection of more than 2,000 works, as well as his own artistic production, a permanent place of display. These two museums are examples of two different types of museum foundations: one is a private initiative, the other a publicly founded institutional museum. They are also only two examples of new Swedish art museums opened around the middle of the 20th century. A number of county museums have focused on art in their collections and a number of donor museums/artists' homes also opened at this time. Swedish art museums are a largely unexplored area and the art sociology perspective used in this study will provide results both for basic knowledge in the area and serve as a basis for further analysis of the role of art museums in society yesterday, today and tomorrow.