In early 1937, General Francisco Franco launched two more (unsuccessful) attempts to encircle Madrid: in January-February at Jarama, where the Nationalists failed to defeat the Republicans which would have cut off the Madrid-Valencia Road, and in March 1931 at Guadalajara, located northeast of Madrid, where the combined Nationalist-Italian forces were routed by the Republicans.
(Taken from Spanish Civil War – Wars of the 20th Century – Vol. 3)
Battle of Madrid Consequently, Republican forces strengthened Madrid’s defenses in anticipation of the Nationalist offensive. In October 1937, Soviet weapons began to arrive in Republican Spain, which by now was led by Prime Minister Francisco Largo Caballero who had succeeded in stabilizing the crisis in government caused by the outbreak of war.
In early November 1936, the Nationalists attacked Madrid along two fronts: from the west led by General Franco, and from the north led by General Mola. Providing air support was the Condor Legion, which wreaked havoc on towns and villages along the Nationalist advance. Also in November 1936, Germany and Italy recognized General Franco’s regime as the legitimate government of Spain.
In anticipation of the Nationalist offensive, on November 6, the Republicans moved their seat of government from Madrid to Valencia. On November 8, the battle for Madrid began. Nationalist forces crossed the Manzanares River after heavy fighting and occupied sections of University City, located north of Madrid. Resistance intensified, as the Republican defenders were buoyed up by the arrival of the first units of the International Brigades. The Republicans had 40,000 fighters (outnumbering the Nationalist attackers by a ratio of 2:1). Republican forces, however, mostly consisted of separate militias that had been organized by socialists, communists, and other pro-government groups.
From documents captured before the battle, the Republicans had learned of the Nationalists’ order of battle, and therefore reinforced the areas that were expected to be attacked. Consequently, the Nationalist offensive was stopped north of the capital. In the following days, Republicans launched a counter-attack which, however, failed to dislodge the Nationalists.
By November 23, the battle lines had settled into a
stalemate, and Nationalists held three-quarters of University City. In the midst of the battle, the Republican
government executed about 1,000 right-wing civilians who were suspected of
spying for the enemy. Shortly after the
battle ended, Republican military authorities merged the various militias into
a unified army called the People’s Republican Army (Spanish: Ejército Popular de la República
).
The Nationalists experienced great losses in the Madrid offensive. As a result, General Franco abandoned his plan to take the city by force and instead began a siege of the capital. In December, the Condor Legion carried out bombing runs on Madrid, killing some 200 civilians and generating international condemnation. In an attempt to encircle the capital, General Franco moved his forces northeast of the city, which led to the Battle of Corunna Road, where both sides suffered heavy casualties. In the encounter, the Nationalists made some territorial gains but failed to surround the capital.
In early 1937, General Franco launched two more (unsuccessful) attempts to encircle Madrid: in January-February at Jarama, where the Nationalists failed to defeat the Republicans which would have cut off the Madrid-Valencia Road, and in March 1931 at Guadalajara, located northeast of Madrid, where the combined Nationalist-Italian forces were routed by the Republicans.
In turn, Republican counter-attacks aimed at lifting the siege on Madrid also ended in failures. In the first of these offensives, which led to the Battle of Brunete in July 1937, Republican forces gained territory but only after suffering considerable losses, and then were thrown back by a fierce Nationalist counter-attack. Then at Zaragoza in December, Republicans launched a major offensive to pre-empt a Nationalist attack on Madrid; in the resulting two-month Battle of Teruel, the Nationalists turned back the attack and gained control of Teruel. The casualty rate at Teruel was one of the highest in the war: the combined number of dead, wounded, and captured was 140,000 soldiers.
Because of the Nationalist setbacks in Madrid, General Franco turned his attention to other fronts. In February 1937, the Nationalists, reinforced by newly arrived Italian forces, attacked and captured weakly defended Malaga, and thereafter brought the whole of southeastern Spain under Nationalist control. General Franco particularly wanted to complete the conquest of northern Spain, and with it, the prized mineral and industrial resources of Biscay, Santander, and Asturias. Not only would the conquest deprive Republicans of valuable resources, it would also be a strong incentive for the Germans (who were looking for new sources of raw materials for war production) to continue providing weapons to the Nationalists.
In March 1937, the Nationalist invasion of Biscay began, which was supported by the Condor Legion carrying out bombing raids on Durango and Guernica. The attack on Guernica on April 26, 1937, which destroyed three-quarters of the town, shocked the international community and generated widespread condemnation against Germany. With Bilbao’s fall on June 19, Biscay Province came under Nationalist control.
Santander Province, which was weakly defended, fell on September 1 after two weeks of fighting. The Republican government had launched many counter-attacks in southeast and central Spain to take the pressure from the beleaguered north, which all failed because of strong and determined Nationalist defenses. At the height of the Nationalists’ northern offensive, General Mola, the over-all commander of the operation, was killed in a plane crash on June 3, 1937. The northern campaign ended on October 21, 1937, when Nationalist forces entered Gijon, bringing Asturias Province under their control.
General Franco now controlled western Spain and about two-thirds of the country. With the Nationalists firmly in possession of Teruel and threatening to advance east to the coast, in November 1937, the Republicans transferred their seat of government from Valencia to Barcelona. Earlier in May 1937, with Juan Negrin becoming Prime Minister, the Republican government became decidedly pro-Soviet, with Marxist politicians holding many Cabinet positions. Soviet influence became dominant because the Soviet Union provided weapons that were keeping the Republican government afloat. Also under instructions from Moscow, agents of the NKVD (Narodnyy Komissariat Vnutrennikh Del, the Soviet Union’s state security agency, arrived in Spain, ostensibly to weed out and eliminate fascists in the general population; these agents, however, also targeted socialists, anarchists, and anti-Stalin communists.
The Republican government also was undermined by its various conflicting constituent ideologies: leftist republicans, socialists, communists, and anarchists. This tenuous alliance led to a backlash in the Barcelona May Days, when in May 1937, hostilities broke out in Barcelona between Republican forces and the anarchist militia, producing a “civil war within a civil war”. After five days of fighting, the anarchists were defeated, which also ended the de facto economic control of Barcelona and Catalonia by the anarchist trade union CNT-FAI (Confederación Nacional del Trabajo and Federación Anarquista Ibérica.
In March 1938, the Nationalists began their offensive into Aragon, where the Republican Army was experiencing a weapons shortage because of the previous year’s fighting. The Nationalists attacked along a broad front, from the Ebro River in the north to Vivel del Rio in the south. The surprised Republicans fell back, their retreat soon turning into a rout and units blaming each other for the emerging disaster. The rapid Nationalist advance reached Belchite, from where a salient formed from Gaspe to Montalban. On March 2, Zaragoza and Huesca were taken, and the Nationalists soon entered western Catalonia.
General Franco stopped his offensive into Catalonia because of concerns that France might intervene. Instead, he pushed south, where on April 16, the first Nationalist units reached Vinaros on the Mediterranean coast. In the following days, the Nationalists extended their control of the coastline.
The remaining Republican territory was now cut into two, with Barcelona and Catalonia geographically separated from Madrid, Valencia, and the rest of central and eastern Spain. The Republicans offered to open peace talks with the Nationalists, an offer that was rejected by General Franco, who demanded the government’s unconditional surrender.
On July 18, 1938, Nationalist forces attacked Valencia but were stopped by strong Republican resistance north of the city. To take the pressure from Valencia, on July 24, the Republicans in Catalonia attacked southwest and crossed the Ebro River into Nationalist territory, starting the Battle of the Ebro. This battle, fought from July to November 1938, became the Republicans’ last major attempt at reversing the tide of war. The Republican Army had been replenished with the arrival of new Soviet arms from France, which had reopened the Spanish border to allow the movement of imported weapons that had accumulated since the Non-Intervention Agreement.