Spanish Civil War: Key Phases and Battles (1936-1939)
The coup was prepared long before. The murders of July 12th and 13th anticipated the uprising, which began on July 17th in Melilla and on July 18th, 1936, on the mainland, lasting until the 21st.
In March 1936, General Emilio Mola presented several drafts for an anti-Republican insurrection that was to be led by General Sanjurjo, who was exiled in Lisbon. The plan involved a declaration of war committed by officers and captains general.
The military coup was coordinated by General Mola from Pamplona, since Sanjurjo was killed in a plane crash. The most influential figures were Mola in Navarra, and Franco in the south. Also prominent were Generals Yagüe, Queipo de Llano, and Goded.
Spain was divided into two camps:
- Nationalist (Rebel) Side: Made up of rural and less populated areas. This side benefited from foreign intervention (German and Italian) and military discipline, which gave significant strength to the Army of Africa (Moroccan troops).
- Republican Side: Composed of the industrialized areas and more important cities. It was characterized by a lack of military organization, which delayed the formation of a strong army.
Phase 1: War of Columns (July 1936 – March 1937)
On July 18th, Franco’s troops crossed the Strait of Gibraltar with German and Italian aid. They dominated Western Andalusia and Extremadura. The goal was to move towards Madrid. General Yagüe took Badajoz after overcoming resistance from Republican defenders, many of whom were subsequently executed in the bullring.
Franco moved through the Tagus valley, conquered Talavera and Toledo, relieving the besieged Alcázar, which was valuable for his appointment in October 1936 in Burgos as Head of State.
Between January and March 1937, the siege of Madrid occurred. Madrid was defended by the Defence Council led by General Miaja, as the government of Largo Caballero had moved to Valencia. Fighting occurred in the University City (Casa de Campo campus). Three major Nationalist offensives against Madrid failed: the Battle of the Corunna Road (northwest), the Battle of Jarama (southeast), which marked a significant Republican stand, and the Battle of Guadalajara (northeast), where Italian forces suffered a major defeat and fled in disarray.
In February, the Battle of Malaga occurred, involving Italian troops as a diversionary tactic, resulting in a Nationalist victory. This stage resulted in the stabilization of fronts. Madrid’s defense held, aided by international support. Franco then shifted focus to conquering the North.
Phase 2: The War in the North (March – October 1937)
The objective for the Nationalists was to capture the industrial area. The Nationalist army received aid from German air support, including the infamous bombings of Durango and Guernica, and conquered the Cantabrian coast (Basque Country, Santander, Asturias).
Republican offensives launched from the center (Battle of Brunete, Battle of Belchite) failed to relieve pressure on the North or significantly distract Franco’s troops.
Phase 3: Advance to the Mediterranean (Oct 1937 – Dec 1938)
The Republicans launched an offensive in Lower Aragon, initially capturing Teruel. However, the Nationalists quickly recaptured the city and then advanced towards the Mediterranean Sea, reaching Vinaròs. This split the Republican territory in two, isolating Catalonia.
Led by Enrique Lister, the Republicans reacted with a major offensive, the Battle of the Ebro. It became a brutal battle of attrition lasting three and a half months. The victory ultimately went to the Nationalists. The battle resulted in heavy casualties for both armies, and its outcome largely decided the war in favor of the Nationalists.
Phase 4: Catalonia Offensive & War’s End (Dec 1938 – Apr 1939)
After the Battle of the Ebro, Franco launched the Catalonia Offensive. The Republican government had moved there in October 1937. As Nationalist forces advanced, hundreds of thousands of Spaniards fled into exile across the Pyrenees border. Among the refugees were prominent figures like the poet Antonio Machado, Martínez Barrio, and President Manuel Azaña, who resigned. Foreign governments began recognizing the Franco regime.
However, the Republican armies in the central-southern zone maintained their opposition for two more months. Prime Minister Negrín returned to Madrid, determined to organize resistance, hoping for either a negotiated peace or the outbreak of a wider European war (World War II). This stance triggered the Casado coup in March 1939 in Madrid. Colonel Casado established a National Defence Council (including Julián Besteiro), seeking to negotiate peace with Franco, who demanded unconditional surrender. This led to a brief internal civil conflict within the Republican side in Madrid between Negrín’s supporters and Casado’s council forces. Franco’s troops then occupied Madrid and Valencia days later, followed by the remaining territory. From his headquarters in Burgos, General Franco announced the end of the war on April 1st, 1939.