Spanish coup of July 1936 in the context of "Causes of World War II"

The Spanish Civil War (Spanish: guerra civil española) was fought from 1936 to 1939 between the Republicans and the Nationalists. Republicans were loyal to the left-leaning Popular Front government of the Second Spanish Republic and included socialists, anarchists, communists, and separatists. The opposing Nationalists who established the Spanish State were an alliance of fascist Falangists, monarchists, conservatives, and traditionalists supported by Nazi Germany and Fascist Italy and led by a military junta among whom General Francisco Franco quickly achieved a preponderant role. Due to the international political climate at the time, the war was variously viewed as class struggle, a religious struggle, or a struggle between dictatorship and republican democracy, between revolution and counterrevolution, or between fascism and communism. The Nationalists won the war, which ended in early 1939, and ruled Spain until Franco's death in November 1975.

The war began after the partial failure of the coup d'état of July 1936 against the Popular Front government by a group of generals of the Spanish Republican Armed Forces. The Nationalist faction consisted of right-wing groups, including Christian traditionalist party CEDA, monarchists, including both the opposing Alfonsists and the religious conservative Carlists, and the Falange Española de las JONS, a fascist political party. However, rebelling units in almost all important cities did not gain control, leaving Spain militarily and politically divided. The rebellion was countered with the help of arming left-wing social movements and parties and formation of militias, what led to rapid socioeconomic and political transformation in the Republican zone, referred to as the Spanish Revolution. The Nationalist forces received munitions, soldiers, and air support from Fascist Italy and Nazi Germany while the Republican side received support from the Soviet Union and Mexico. Other countries, such as the United Kingdom, France, and the United States, continued to recognise the Republican government but followed an official policy of non-intervention. Despite this policy, tens of thousands of citizens from non-interventionist countries directly participated in the conflict, mostly in the pro-Republican International Brigades.

The phrase Spanish Republic at war refers to the Second Spanish Republic during the Civil War of 1936–1939. It represents the last stage in this war's history. The territory that remained under its control after the coup of July 1936—which was called the republican zone or the loyalist zone—gradually reduced as the rebel zone spread, until it was finally occupied in its entirety by the Francoist side (which had referred to the areas as the red zone throughout the civil war).

During this time, there were three consecutive governments: the one presided over by José Giral, from Republican Left, although during his short term (July–September 1936), real power was actually in the hands of the hundreds of committees that were created when the social revolution of 1936 broke out. The next government was presided over by Francisco Largo Caballero, the leader of the Spanish Socialist Workers' Party (PSOE) and the Unión General de Trabajadores (UGT), one of the two trade unions that had led the revolution. Finally, the third government was presided over by Juan Negrín, also from the PSOE, as a consequence of the fall of Largo Caballero's government after the events of May 1937. Negrín governed until early March 1939, when Colonel Segismundo Casado's coup took place, putting an end to the Republican resistance and giving way to the victory of the rebel faction led by General Francisco Franco.

The Spanish Revolution was a social revolution that began at the outbreak of the Spanish Civil War in 1936, following the attempted coup to overthrow the Second Spanish Republic and arming of the worker movements and formation of militias to fight the Nationalists. It featured takeover of power at local levels by the Spanish workers' organizations and social movements, seizure and reorganization of economic facilities directed by trade union groups and local committees, and widespread implementation of socialist, more narrowly, libertarian socialist and anarchist organizational principles throughout various portions of the Republican zone, primarily Catalonia, Aragon, Andalusia, and parts of the Valencian Community.

Much of the economy of Spain was put under worker control; in anarchist strongholds like Catalonia, the figure was as high as 75%. Factories were run through worker committees, and agrarian areas became collectivized and run as libertarian socialist communes. Many small businesses, such as hotels, barber shops, and restaurants, were also collectivized and managed by their former employees. The revolutionary principles implemented with the revolution continued to evolve as much as the Republican zone existed, until the end of the civil war with the victory of the Nationalists.

The Communist Party of Spain (Spanish: Partido Comunista de España; PCE) is a communist party that, since 1986, has been part of the United Left coalition, which is currently part of Sumar. Two of its politicians are Spanish government ministers: Yolanda Díaz (Minister of Labour and Social Economy) and Sira Rego (Minister of Youth and Children).

The PCE was founded by 1921, after a split in the Spanish Socialist Workers' Party (Spanish: Partido Socialista Obrero Español; PSOE). The PCE was founded by those who opposed the social democratic wing of the PSOE, because the social democrat wing did not support the PSOE's integration in the Communist International founded by Vladimir Lenin two years prior. The PCE was a merger of the Spanish Communist Party (Spanish: Partido Comunista Español) and the Spanish Communist Workers' Party (Spanish: Partido Comunista Obrero Español). The PCE was first legalized after the proclamation of the Second Spanish Republic in April 1931. The republic was the first democratic regime in the history of Spain. The PCE gained much support in the months before the Spanish coup of July 1936, which marked the beginning of the Spanish Civil War, and it was a major force during the war as well. The Republicans lost, and Franco established a military dictatorship, under which the PCE was one of the most heavily repressed parties, with specific laws banning communist parties, among others.

Francisco Largo Caballero (15 October 1869 – 23 March 1946) was a Spanish politician and trade unionist who served as the prime minister of the Second Spanish Republic during the Spanish Civil War. He was one of the historic leaders of the Spanish Socialist Workers' Party (PSOE) and of the Workers' General Union (UGT). Although he entered politics as a moderate leftist, after the 1933 general election in which the conservative CEDA party won the majority, he took a more radical turn and began to advocate for a socialist revolution, materialized with the failed Revolution of 1934 in Asturias.

After the victory of the Popular Front in the 1936 Spanish general election and following the July coup, Caballero served as prime minister of Spain during the Spanish Civil War from 4 September 1936 until 17 May 1937. Exiled in France following the Republican defeat in 1939, Caballero was imprisoned in the Sachsenhausen concentration camp after the Nazi invasion of France.

The Legionary Air Force (Italian: Aviazione Legionaria, Spanish: Aviación Legionaria) was an expeditionary corps from the Italian Royal Air Force that was set up in 1936. It was sent to provide logistical and tactical support to the Nationalist faction after the Spanish coup of July 1936, which marked the onset of the Spanish Civil War.

The corps and its Nazi German allies, the Condor Legion, fought against the Spanish Republic and provided support for the Italian ground troops of the Corpo Truppe Volontarie. They served from August 1936 to the end of the conflict, in March 1939. Their main base of operations was on Mallorca, in the Balearic Islands.