Its origins lie in a small group of former members of Lutte Ouvriere who left that group in 1974 expecting to join a larger group, Union Ouvrier, who had broken from LO the previous year. They found that UO had already disintegrated with its members going in many directions. Therefore they formed a group of their own, named Combat Comuniste.
Combat Comuniste existed for a period but as a tiny grouping, it had many problems and was somewhat heterogenous which led to its failure. By this point some of the members of CC had been won over to the positions of the International Socialists (UK). Therefore they sought to win other militants to their views prior to launching an independent group of their own and joined the Ligue Communiste Revolutionnaire to further that aim. After a period they were to leave and found the Socialisme Internationale group.