The future of the republic depended not only on its right-wing enemies but also on the labor movement. In the case of the Socialist Party (PSOE), the “revolutionary” left faction, led by Francisco Largo Caballero, refused to repeat the experience of the Republican-Socialist government of 1931–33 and insisted that the Socialists (PSOE) should not participate in the new government, leaving it to the Republicans to “complete the bourgeois revolution.” This simplistic view of Marxism meant that Largo Caballero and his followers had no strategy for seizing power; instead, they were to wait passively for the Republicans to pave the way for a socialist government.

In contrast, the more social democratic faction led by Indalecio Prieto, supported by the Communist Party (PCE), argued for the need to return to a coalition government to complete the Republican reformist program. It was this latter position that would be adopted by the Socialist movement in the midst of the Civil War. The Left, having lost part of its base to Stalinism, particularly the Socialist Youth (FJS), which would merge with the Young Communists to form the JSU (Juventud Socialista Unificada), was overtaken by events and ultimately accepted the same position as its social democratic rivals.

On the eve of the civil war, the anarcho-syndicalist Confederación Nacional del Trabajo (CNT) still wielded considerable influence within the most significant labor movement in the Spanish state, in Catalonia, and maintained a very strong presence in Andalusia, Aragon, and Valencia. Furthermore, in Asturias and Madrid, where the Socialists had historically been the dominant force among organized workers, the CNT enjoyed sizable minority support.

Inside the CNT, activists and union leaders were divided between anarcho-syndicalists and various radical anarchist factions, the most important of which was the Federación Anarquista Ibérica (FAI). One thing all these factions had in common was their apoliticism. However, weakened by repression and ideologically divided, the CNT would adopt a less intransigent stance in its relations with the Left during the first months of 1936, a move that would prove to be a prelude to its direct participation in government during the civil war.

During the February 1936 elections, to secure the release of its thousands of imprisoned members, the CNT did not organize a campaign of abstention, as it had done in 1933, and this de facto call to vote would contribute to the Popular Front’s victory. In May 1936, the CNT held its fourth congress in Zaragoza. It would prove to be a milestone in the union’s history.

Faced with the bloody repression of the Asturian commune in October 1934, delegates called for a revolutionary alliance with the Socialist Unión General de los Trabajadores (UGT) as a first step toward social revolution. But the congress also revealed the limitations of the CNT’s turn away from its apolitical sectarianism. While there was a long and abstract debate on the nature of libertarian communism, there was no discussion of the political situation, especially the threat of a military coup.

The newly formed Partido Obrero de Unificación Marxista (POUM) also defended workers’ unity but through the reorganization of the Workers’ Alliances, which had played a key role in the revolutionary movement of 1934. The POUM contrasted the Workers’ Alliance, seen as essential for smashing capitalism, with the Popular Front, an electoral alliance subordinated to petty-bourgeois republicanism.

At the same time, it identified the absence of a mass revolutionary party as having been central to the defeat of the revolutionary movement in 1934. The POUM hoped to win over the most radical sectors of the Socialists, especially the youth. The FJS’s falling under Stalinist influence in the spring of 1936 would deal a fatal blow to those hopes.

The revolution that broke out in response to the military uprising in July 1936 marked the end of the European revolutionary cycle that had begun with the Bolshevik victory in 1917. In a matter of days, as the leader of the POUM, Andreu Nin, would insist in September 1936, the working class, arms in hand, had resolved the “fundamental problems” of the democratic revolution that the “liberal bourgeoisie” had failed to resolve in five years. Grossly unequal land ownership had been swept aside with collectivization or redistribution; the power of the church and the army had been destroyed, and Catalonia had ceased to be subordinated to a centralist state. But the working class, Nin clamed, was not fighting for a democratic republic but for socialism.

The cornerstone of this revolution was a unique experiment in workers’ self-management with the collectivization of industry and land. In many cases, the takeover of companies or land was a spontaneous process and was only subsequently supported by the workers’ organizations. Urban collectivization went furthest in Catalonia, where half of Spain’s industry at the time was concentrated. In the Valencia region, collectivization was also widespread, especially in agriculture.

The best-known agricultural collectives were those organized by anarchists in eastern Aragon. And although the presence of CNT militias in the area would influence their development, the initiative was often local, especially in towns where libertarian communism had been briefly established during the anarchist uprising of December 1933. Agrarian collectivization was also present in Andalusia and New Castile. Elsewhere with the notable exception of the Basque Country, the working class played a decisive role in the economy through different forms of workers’ control and the expropriation of workplaces and farms abandoned by supporters of the rebels.

The revolution also meant the widespread occupation of urban space, with buildings being seized and converted into schools, hospitals, popular restaurants, and the headquarters for antifascist organizations. As Mary Nash has argued, the revolution and the war represented for many women “a breakdown in the traditional confinement of women to the home and gave them public visibility.” They entered political life for the first time, joining antifascist women’s organizations en masse, working in factories, and, in a minority of cases, participating in the armed struggle.

At the heart of the resistance to the military rebels were the workers’ organizations, and not only in the areas where the social revolution was strongest. Throughout what would become the Republican zone, unions and workers’ parties quickly organized militias to fight the rebels. By the summer of 1936, there were already some 150,000 militiamen (and a minority of women) fighting on various fronts.

Faced with the military superiority of the rebels, who were heavily supplied by the fascist powers, the main parties of the Popular Front (Republicans, Socialists, and Communists) argued that it was necessary to present the war as a defense of bourgeois democracy in order to maintain the support of the middle classes and to secure military aid from the Western democracies. This was a position that meant suppressing, or at least concealing, the social revolution underway in much of the Republican zone.

Both in historiography and at the time, the left Republican parties have been seen as representing the “middle classes” or at least a sector of them. The fact that these parties played a central role in the republican governments of 1931 and 1936 has reinforced the idea of their political importance. However, their social and electoral base was limited. Outside of Catalonia, the only place where left republicanism enjoyed massive support (through Esquerra Republicana de Catalunya), it had a narrow social base, consisting mainly of the urban petty bourgeoisie and very specific sectors such as schoolteachers.

The electoral results of the Left Republicans clearly illustrate the limitations of their support. In 1931, excluding Catalonia, 111 Left Republican deputies were elected in coalition with the PSOE and the moderate republican Radical Party, and in 1936, 129 were elected as part of the Popular Front. In 1933, without being part of a national coalition, the Left Republicans won only fourteen seats (compared to twenty-one in Catalonia), nine of them thanks to local agreements with the Radicals and five due to local support from the PSOE.

At an international level, the republic’s seemingly natural allies, the liberal democracies, with the notable exception of Mexico, not only abandoned the legitimate government by refusing to send it the weapons necessary for its defense but also promoted the farce of the “nonintervention” policy, which would result in the almost total isolation of loyalist Spain (as the republic was known). The participation of Germany and Italy in the nonintervention committee would be the clearest example of the cynicism of this infamous agreement.

Neither France nor Great Britain had any interest in supporting an apparently weak government in a context of intense political and social radicalization. The French Popular Front government, under pressure from the ruling classes, the army, and British imperialism, quickly backed down from sending arms to the republic. The British government viewed the Left Republican leader, Manuel Azaña, the first Popular Front prime minister, as the “Kerensky of Spain.” When the Civil War began, it believed that “Bolshevism” was on the verge of seizing power. Statements abounded among its ministers about how Francisco Franco was the best option for protecting British imperialist and capitalist interests.

With the degeneration of the Russian Revolution and Joseph Stalin’s rise to power, the communist parties had become completely subordinate to Moscow’s political needs. The Comintern’s shift toward the Popular Front policy was driven, above all, by the need to contain the threat that Nazi Germany posed to the very survival of the USSR. This threat made it urgent to forge, at the international level, an alliance with the democracies, especially France, against the fascist powers. The Popular Front was thus the national expression of Soviet foreign policy, and the uniform adoption of this new orientation by the communist parties at that time was not based on any analysis of the specific sociopolitical situation in each country.

However, in contrast to the disastrous previous line that had identified the socialist parties as “social fascists” and the greatest danger to the working class, the Popular Front responded to the need to confront the threat from the far right and would result in a surge in communist influence in many countries, including Spain. During the Civil War, the PCE would become the most powerful political party in the Republican zone. By mid-1937, it had around 300,000 members, ten times more than before July 1936, while its Catalan equivalent, the Partit Socialista Unificat de Catalunya (PSUC), more than 50,000, and the JSU about 250,000.

There were several reasons for this growth in influence. The staunch defense of the Popular Front by the Communists attracted to the party newly politicized people opposed to the military uprising and fascism, including petty-bourgeois sectors frightened by the “excesses” of the revolution and the attacks on private property. By defending military centralization and iron discipline, the Communists also won the support of many professional military officers who had remained loyal to the republic. But above all, the USSR’s military support for the republic contributed to the rise in the PCE’s prestige.

A factor often overlooked in explaining the growth of the Communists’ influence in Spain was the persistence of their image as “the party of the Russian Revolution” and their self-identification as revolutionaries. The fact that the PCE, despite its commitment to defending republican democracy, spoke of the need for a “new kind of democracy,” a “people’s revolution,” and a “national revolutionary war” reflected the difficulties the party had in the context of the political and social realities in the Republican zone.

The extensive use of Soviet imagery and revolutionary methods to mobilize the population of Madrid in November 1936 was another example of the Communists’ seemingly ambiguous relationship with bourgeois democracy. From there, it was not difficult to conclude that the Popular Front was a necessary tactical interlude, a preliminary phase leading up to the establishment of socialism. Such ambiguities help explain the appeal of Stalinism to a significant sector of the FJS.

Ultimately, only the PCE (in Catalonia, the PSUC), with its discipline and “Leninist” structure, and not the liberal and reformist factions, was capable of both putting an end to the social revolution underway in the Republican zone and leading politically the Popular Front’s war effort.

After the defeat of the military uprising in nearly two-thirds of Spain, power was exercised by countless local antifascist committees, mostly made up of the Popular Front parties, the UGT, and the CNT. In Catalonia, the committees reflected the influence of the revolution and were often dominated by the anarchists and the POUM. Few of the committees were elected by the local population but tended to be made up of delegates nominated by the different antifascist organizations.

To overcome the lack of coordination and the fragmentation of power during the first weeks in the Republican zone, various types of bodies were organized at the regional and provincial levels, almost all of which were supported by the local Popular Front, along with the CNT. Their autonomy and radicalism varied from place to place. The most important of these was the Central Committee of Antifascist Militias (CCMA) in Catalonia, formed on July 21.

Despite having a Popular Front majority, the CCMA’s decisions reflected the strength of the revolution. In addition to military organization, the Catalan committee took the first steps to control the economy, organizing food distribution, freezing the bank accounts of those who had supported the uprising, and implementing measures to help workplaces already in workers’ hands to continue paying wages.

In much of the rest of the Republican zone, committees were formed that, like the CCMA, effectively held power during the first weeks of the war. The political orientation of most of these committees did not always reflect the politics of the Popular Front, despite the fact that its supporters usually made up most of the delegates. For example, in Aragon, Cartagena, Gijón, Málaga, and Valencia the committees, dominated by the unions, acted in an openly revolutionary fashion.

But with the fragmentation of power, the revolution could not fully triumph. Faced with this reality, the future of the revolution depended on the CNT, whose power appeared unassailable in the first weeks of the Civil War and soon would double its membership to reach some 1,500,000. But the anarchists rejected on principle the seizure of power.

The revolution existed for them in the sense that the working class controlled the streets, the factories, and the land. “Power” would be exercised below in local communes or the workplace. But the workers’ organizations, for example, did not control communications, foreign trade, or the banking system. Above all, with the formation of the People’s Army of the Republic in the fall of 1936, they lost control of the key element of the war and the revolution: the armed forces.

The dilemma the anarchists faced with the vacuum left by the near collapse of the republican state would soon become apparent. At a hastily called meeting of Catalan CNT delegates in Barcelona on July 21, Juan García Oliver, one of the most influential leaders of radical anarchism, argued that the CNT faced two alternatives: “going all out,” which would mean establishing “an anarchist dictatorship,” or collaborating with the other antifascist forces. Since “a dictatorship” was anathema to the anarchists, and given the significant presence of other forces (especially the Socialists), particularly outside of Catalonia, they opted for “collaboration.”

The anarchist leaders would quickly find themselves trapped in the contradiction between their defense of the revolution and their complicity with the bourgeois state, or what was left of it. The dichotomy was not between “dictatorship” and “collaboration” but between workers’ unity, extending beyond the ranks of the anarchists, with the aim of seizing power, or subordination to the Popular Front, which would sooner or later spell the end of the revolution.

Opposed to creating another state, the anarchists ended up collaborating with the existing state or, to be more precise, with the reconstruction of the republican state. In early November 1936, as the military situation grew increasingly critical, in an unprecedented move, four anarchists became ministers in the Republican government.

The counterrevolutionary process within the Republican zone would reach its peak with the street fighting in early May 1937. The formation a week later of a government headed by the moderate socialist Juan Negrín, without the participation of the anarchists, represented the definitive consolidation of the bourgeois state.

It also led to the suppression of the POUM, victim of a fierce campaign of slander by the Stalinists. The last bastion of the revolution, the anarchist-dominated Council of Aragon, was dissolved in August. In February 1938, the CNT, now fully committed to collaborating with the republican state, returned to the government.

Was there an alternative to the Popular Front’s approach of waging a war in defense of democracy at the expense of social revolution? The Republican government’s military strategy rejected the use of unorthodox or revolutionary tactics, due in part to its need to maintain control of the political situation within its territory, as well as to present itself to the world as a liberal government. However, given the enemy’s significant material advantage, adherence to an orthodox military strategy had little chance of success.

The idea that the Popular Front, and the suppression of the revolution, was purely due to the republic’s military needs is a fallacy. The Popular Front’s policies, especially its subordination to imperialist interests, had military consequences. For example, the Spanish fleet, which was under the control of the sailors, was withdrawn from the Strait of Gibraltar from the very beginning due to pressure from the British government, thus giving the rebels free rein to transport thousands of troops from North Africa to the Iberian Peninsula. Another case in point is the refusal, out of concern for not harming French interests, to declare Morocco’s independence and support a nationalist uprising behind the fascist lines.

An alternative strategy would have included the mass mobilization of the population (as was the case during the siege of Madrid in November 1936), a defensive, positional war, and the launching of more limited raids combined with guerrilla warfare, thereby avoiding massive clashes between two armies with markedly unequal capabilities. One can only speculate, of course, whether a strategy of revolutionary war could have succeeded, although the defense of Madrid is illustrative in this regard.

Another problem facing the revolution was an unfavorable international situation, in which both the communist and social democratic parties wielded great influence. It is impossible to know what impact the existence of a revolutionary power in Spain would have had on the labor movement beyond its borders. The precedent of 1917 raises the possibility that it might have served as a catalyst and, as a result, led other political currents to exert greater influence on the class struggle.

In the historiography of the Civil War, the division among the antifascist forces is often presented as a split between those who wanted to prioritize the war (Communists, Republicans, and Socialists) and the CNT and the POUM, who placed the interests of the revolution above those of the war: a choice between war or revolution. This was never the case. Both the CNT and the POUM defended the need to wage war and carry out the revolution simultaneously — to wage a revolutionary war.

The two were intrinsically linked. The POUM had a clear military policy that called for the creation of a revolutionary army, modeled on the Soviet Red Army during the Russian Civil War. But such an army could not be built without a revolutionary government based on democracy from below, on committees of workers, peasants, and militia members.

The POUM maintained that, to consolidate the revolution, at least in Catalonia, the working class had to seize power. But without the CNT, such a goal was impossible. Convincing the CNT, or at least part of it, of this point very quickly became the POUM’s primary political concern. However, as we have seen, it had to overcome the conviction held by the anarchists that any form of “power” or revolutionary state would inevitably lead to dictatorship.

Ultimately, what was sorely lacking in the Spanish Revolution was a revolutionary organization with the strength necessary to have led the seizure of power. There were several obstacles preventing the POUM, the “only party of the revolution,” according to Andreu Nin, from becoming such an organization. Its lack of a base outside Catalonia and its short history — it had been formed just a year earlier — were obstacles that were difficult to overcome. Without national political leadership, the revolution was doomed to defeat.