When the Spanish Civil War turned inward: The bloody May Days of 1937
In May 1937, Barcelona became a battlefield not between fascists and republicans, but between the very factions meant to be allies. For six days, anarchists, communists, and government forces fought in the streets, exposing a deep, fatal fracture within the Republican side that would ultimately help tear the republic apart.
The May Days, or May Events, erupted between 3 and 8 May 1937, centered in Barcelona. The conflict pitted revolutionary groups—primarily the anarchist CNT and the anti-Stalinist POUM—against the Republican government, the Catalan Generalitat, and the Communist Party of Spain (PCE). While all sides ostensibly fought the Francoist rebellion, the anarchists and the POUM insisted that the war and the social revolution were inseparable. Conversely, the PCE and the PSUC argued that prioritizing revolution was counter-revolutionary, advocating for a centralized government and a unified military command to win the war first.
Tensions had been simmering for months. By spring 1937, the PCE was actively vilifying the POUM as covert Nazi agents, while anarchist patrols continued to operate independently of the government. The spark ignited on 3 May when government forces attempted to seize the Telefónica central exchange, which was legally occupied by an anarcho-syndicalist committee. Anarchist workers opened fire, and within hours, barricades appeared across the city. For nearly a week, the city was paralyzed by rifle and machine-gun fire, with both sides fortifying buildings and requisitioning hotels.
The fighting caused hundreds of casualties, though estimates vary wildly. While some contemporary reports claimed 500 deaths, modern academic research by historians like Josep Solé i Sabaté and Joan Villarroya suggests a lower figure of approximately 235 fatalities. The events effectively ended the revolutionary experiment in Catalonia. The POUM was soon outlawed, its leaders arrested, and the anarchist movement lost its previous influence. The crisis also led to the fall of Prime Minister Francisco Largo Caballero’s government, marking a decisive shift toward Marxist-Leninist influence within the Republic.
The May Days remain a haunting example of internal discord during wartime. The inability of the Republican factions to reconcile their visions—one favoring decentralized revolutionary control and the other a disciplined, central state—crippled their collective defense. By the time the streets returned to a fragile normality, the internal divisions had already inflicted irreparable damage on the Republic’s unity against the rebels.
Source: May Days
