Like the French Force Ouvrière (FO) union, it received financial support from Irving Brown, leader of the international relations of the US AFL–CIO and a CIA contractee.

[1] The CISL is formed on two levels: a vertical one, grouping workers according to employment (such as transport, banks, and teaching), and the confederation itself, representing all categories.

In 1956, owing to CISL initiatives, the latter had separated from the employers' group Confindustria and had formed the Intersind – meant to establish a new base for relation between the state and trade unions.

When the Italian economy sunk in the mid-1960s, CISL suffered an internal crisis as numerous of its branches believed the political function of the union to be incompatible with its labour goals.

The following years proved to be especially tumultuous for Italy as a whole: while traditional trade unionism was being reshaped by the student movement and secondary impact of the decolonization and Third World ideologies, the local scene saw the advent of terrorism of the Red Brigades and the Neo-Fascist Strategy of tension (carried out by the National Vanguard).