A similar Nationalist offensive, the Battle of Guadalajara, was a more significant defeat for Franco and his armies. This was the only publicized Republican victory of the war. Franco used Italian troops and blitzkrieg tactics; while many strategists blamed Franco for the rightists' defeat, the Germans believed it was the former at fault for the Nationalists' 5,000 casualties and loss of valuable equipment.
April and May saw the May Days, infighting among Republican groups in Catalonia. The dispute was between an ultimately victorious government—Communist forces and the anarchist CNT. The disturbance pleased Nationalist command, but little was done to exploit Republican divisions. After the fall of Guernica, the Republican government began to fight back with increasing effectiveness. In July, it made a move to recapture Segovia, forcing Franco to delay his advance on the Bilbao front, but for only two weeks. A similar Republican attack, the Huesca Offensive, failed similarly.
The Battle of Brunete, however, was a significant defeat for the Republic, which lost many of its most accomplished troops. The offensive led to an advance of 50 square kilometres (19 sq mi), and left 25,000 Republican casualties. The Battle of Brunete (6–25 July 1937), fought 24 kilometres (15 mi) west of Madrid, was a Republican attempt to alleviate the pressure exerted by the Nationalists on the capital and on the north during the Spanish Civil War. Although initially successful, the Republicans were forced to retreat from Brunete and suffered devastating casualties from the battle.
A Republican offensive against Zaragoza was also a failure. Despite having land and aerial advantages, the Battle of Belchite, a place lacking any military interest, resulted in an advance of only 10 kilometres (6.2 mi) and the loss of much equipment. The Battle of Belchite refers to a series of military operations that took place between 24 August and 7 September 1937, in and around the small town of Belchite, in Aragon during the Spanish Civil War.
With the surrender of the Republican army in the Basque territory came the Santoña Agreement. The Santoña Agreement, or Pact of Santoña, was an agreement signed in the town of Guriezo, near Santoña, Cantabria, on August 24, 1937, during the Spanish Civil War, between politicians close to the Basque Nationalist Party (Partido Nacionalista Vasco or PNV), fighting for the Spanish Republicans, and Italian forces, fighting for Francisco Franco.
Gijón finally fell in late October in the Asturias Offensive. The Asturias Offensive was an offensive in Asturias during the Spanish Civil War which lasted from 1 September to 21 October 1937. 45,000 men of the Spanish Republican Army met 90,000 men of the Nationalist forces.
The Battle of Teruel was an important confrontation. The city, which had formerly belonged to the Nationalists, was conquered by Republicans in January. The Francoist troops launched an offensive and recovered the city by 22 February, but Franco was forced to rely heavily on German and Italian air support. The Battle of Teruel was fought in and around the city of Teruel during the Spanish Civil War. The combatants fought the battle between December 1937 and February 1938, during the worst Spanish winter in twenty years. The battle was one of the bloodier actions of the war with the city changing hands several times, first falling to the Republicans and eventually being re-taken by the Nationalists. In the course of the fighting, Teruel was subjected to heavy artillery and aerial bombardment. The two sides suffered over 140,000 casualties between them in the two-month battle. It was a decisive battle of the war, as Francisco Franco's use of his superiority in men and material in regaining Teruel made it the military turning point of the war.