This organisation sought to influence the ranks of the larger Workers' Party of Marxist Unification (POUM) and also worked closely with the more left-wing anarchists of the Durruti Column.

, a number of Spanish anti-fascist fighters He was arrested on February 13, 1938[3] but the next year, shortly before the fall of Barcelona, he was able to escape the Monjuic Prison, cross Franco's lines and eventually pass over the border to France.

He made his fate public in an interview with the French Trotskyist newspaper La Lutte Ouvrière published in its February 24 and March 3, 1939, issues.

[5] During the war and immediate post-war years Munis began to have differences with the Fourth International Secretariat based in New York, and with the Socialist Workers Party of the United States.

At the Second World Congress of the Fourth International Munis blocked with Max Shachtman of the Workers Party but was eventually condemned by the Secretariat.

[6] After the war Munis settled in Paris and began publishing a new periodical Revoluciòn, which proclaimed its official break with the Fourth International in November 1948.

[7] Munis also had followers in several other countries and in the late 1970s these were organized into the Revolutionary Workers Ferment with sections in France, Italy, Greece and the United States.