There was not only one
Internationale Situationniste but two groups. The less known one was formed when
Jorgen Nash, Asgar Elde,
Jacqueline de Jong, Katja Lidell, Steffan Larsson and Sardy Strid walked out of the Debord's SI in 1962. They established Nash's villa
Drakabygget near
Halmstad as their headquarters. Because the history of
SI is more or less, rather less, studied from Angloamerican and French point of views, the second SI not so known but it doesn't mean they were inactive.
Of course, Paris-based SI proclaimed that they didn't excactly walk out but were expelled from SI. They were given name "nashists" and defined as follows:
Nashism (French: Nashisme, German: Nashismus, Italian: Nascismo): The term is derived from the name Nash, an artist who seems to be lived in Denmark on 20th century. Known for his attempt to deceive contemporary revolutionary movement and theory. The term suits for all traitors in the struggle against prevailing cultural and social circumstances.
Debord & co. accused nashists that they were interested in nothing but
commercial success and
popularity.
Nash's SI had also some 10-15 members and they were later joined by German artists called SPUR. They published at least two papers, Situationist Times and Drakabygget. They were much more keen on art than their Parisian counterparts but still they were situationists by heart: They just believed that an act is the result of feelings and aroused from them. That's why there's need for (situationist) art in pre-revolution era. Debord thought the opposite and was mocked by Nash: "You feel yourself spiritual only after you have said your prayers."
One may say that Scandinavian Internationale Situationniste was a socialdemocratic version of the situationists of Paris. They based their movement on the secularization of Kierkegaard's situation philosophy, unified with German dialectic, British economics, French claims on societal change and finally on renewed Marx. They called their theory situology and their goal was a situcratic society founded through people's revolution.
It can be consider that the Scandinavian SI was resurrection of dada. They organised happenings and wrote manifests etc. For example, the Mutant-Manifesto says: "A word war is better than a world war." This was the hottest period of Cold War and the Manifesto claimed they refused to cooperate with anyone who can be linked with an atom bomb shelter. In Sweden, they were called quasi-artists who express their artistic traits through beards and dirty clothes. This was an official reply to the situation lived out by Carl Magnus and his friends: They made a tomb on a city square which said: "RIP: Art gallery, cultural scholarships, public artworks, etc."