In 1936, Francisco Franco was appointed General Commandant of the Canaries. He joined the military revolt of 17 July which began the Spanish Civil War. Franco quickly took control of the archipelago, except for a few points of resistance on La Palma and in the town of Vallehermoso, on La Gomera. Though there was never a war in the islands, the post-war suppression of political dissent on the Canaries was most severe.

During the Second World War, Winston Churchill prepared plans for the British seizure of the Canary Islands as a naval base, in the event of Gibraltar being invaded from the Spanish mainland. The planned operation was known as Operation Pilgrim.

Opposition to Franco’s regime did not begin to organise until the late 1950s, which experienced an upheaval of parties such as the Communist Party of Spain and the formation of various nationalist, leftist parties.

During the Ifni War, the Franco regime set up concentration camps on the islands to extrajudicially imprison those in Western Sahara suspected of disloyalty to Spain, many of whom were colonial troops recruited on the spot but were later deemed to be potential fifth columns and deported to the Canary Islands. These camps were characterised by the use of forced labour for infrastructure projects and highly unsanitary conditions resulting in the widespread occurrence of tuberculosis.