In October 1938, from the 16th through the 30th in Barcelona, the FIJL participated in a national plenum of the libertarian movement, which was also attended by members of the Confederación Nacional del Trabajo (CNT) and the Iberian Anarchist Federation (FAI).

[4] During the May Days purge of the Workers' Party of Marxist Unification (POUM) and other anti-Stalinist organisations, which took place in Barcelona towards the end of the Spanish Civil War, many FIJL members were murdered by those acting under Joseph Stalin's orders.

[5] After the Civil War, FIJL acted in two branches: one in exile in Paris, and one secret and illegal domestic organisation under Franco's regime.

[7] The organisation's most famous member was Federico Borrell García, the subject of Robert Capa's most well known photograph, The Falling Soldier.

[12] Today, this FIJL has a presence in Asturias, Cádiz, San Sebastián, Granada, Lorca (Murcia), and Madrid.