The Poster Museum at Wilanów (Polish: Muzeum Plakatu w Wilanowie) is the world’s oldest poster museum. The Poster Museum at Wilanów is part of the National Museum in Warsaw. It was established through a grant of several thousand posters belonging to the National Museum, made by the Museum’s Director, Stanislav Lorentz. The Poster Museum opened in June 1968, becoming the world’s first museum dedicated to this art form.

At its founding, the Museum had 13,000 items in its collection, including around 500 posters preserved from the World War II era. Its collection is continually growing, through gifts from Polish and international donors.

During the mid-20th century, Polish interest in poster art, and poster collecting, grew substantially, influenced by the visual style of national filmmakers such as Andrzej Wajda. Collectors sought posters advertising films, plays, and musicals in particular. Warsaw’s annual poster art competition gained a worldwide reputation, ultimately leading the founding of the Poster Museum in 1968.

More than 55,000 posters are in the collections of the Poster Museum at Wilanów. 30,000 items represent the history of poster art in Poland from 1892 to 2002. The Poster Museum houses one of the world’s largest collections of posters. The Museum rotates its collection through permanent exhibits on Polish poster art and history, foreign poster art, and thematic exhibits.

The Poster Museum is housed in a modern exhibition space erected behind the historic Wilanów Palace, a 19th-century riding school located on the outskirts of Warsaw.

According to Wikipedia