A Vintage Ludwig Mies van der Rohe Barcelona Chair for Florence Knoll The MR90 was designed by Mies van der Rohe for use in the German Pavillion at the 1929 International Exhibition, Barcelona. After the war, limited numbers of the Barcelona chair were hand produced for Florence Knoll. This example is circa 1950 and was produced prior to Knoll gaining licence in 1953. This early model is distinguished by its interlocking hand-screwed chrome frame, which sets it apart from all later mass produced models.