Revolutionary alliance of European avant-garde artists, writers and poets formed at a conference in Italy in 1957 (as Internationale Situationiste or IS). It combined two existing groupings, the Lettrist International and the International Union for a Pictorial Bauhaus. The leading figure was the writer and filmmaker Guy Debord and the group also prominently included the former Cobra painter Asger Jorn. The former Cobra artist Constant was also a member, and the British artist Ralph Rumney was a co-founder of the movement. The IS developed a critique of capitalism based on a mixture of Marxism and Surrealism, and Debord identified consumer society as the Society of the Spectacle in his influential 1967 book of that title. In the field of culture Situationists wanted to break down the division between artists and consumers and make cultural production a part of everyday life. Situationist ideas played an important role in the revolutionary Paris events of 1968. The IS was dissolved in 1972.