The Republican efforts to save the north through offensives from the central zone culminated with their attack on Zaragoza which lasted from August 24 to September 7, 1937. Like the earlier attacks on Segovia, Huesca, and Brunete, it failed to realize the objective of breaking the front, destroying the enemy army, and capturing important towns. In addition, it came too late to save Santander, which fell two days after it began. The Republicans did manage to win some ground in Aragón, but these gains were irrelevant to the overall course of the war.
As was generally the case in the summer of 1937, the Republican offensive began well. The Francoist forces were outnumbered and less well armed. Their strategists had not attached much importance to the Aragón front, especially as the Republican forces there consisted of largely ineffective anarchist militias under the control of the Regional Defence Council of Aragón. But by the time the attack began, things changed. At the beginning of August, units of the Popular Army dissolved the Council by force, and the offensive was carried out by that army’s best units supported by tanks. The Republicans also had overwhelming air superiority, but the efforts of its air force proved uncoordinated and ineffective.
Led by the 45th International Division, the attackers got to within 6 kilometres of Zaragoza but, in the face of the determined Francoist resistance, they were unable to advance any further and surround the city. At Brunete, Franco had halted his northern offensive to send reinforcements. At Belchite, the reinforcements came from the central front.
Following the failure to take Zaragoza, the focus of the offensive moved to a secondary front, but one that would soon become very famous: Belchite. The Republicans had surrounded the town on August 26. The Francoist garrison, which consisted of several thousand men, took up positions in the centre of the city but the Republicans, aware they had little time, decided to attack. The fighting was fierce, at times hand to hand. The Republicans cut the water supply, which added to the hardship of the summer heat. Republican artillery blasted away at Francoist positions, leaving the town devastated. The Republicans took the town on September 6 after a battle that took some 5,000 lives and produced large numbers of prisoners of war.
The Republican victory changed nothing. Its army remained unable to carry out large scale operations with any speed. For the Francoist army, Belchite was a strategic victory which one again showed its defensive capabilities. It was not much different from the Popular Army in this regard, but where it did differ was in its ability to attack in depth and consolidate its gains.
Belchite remained in Republican hands. After the war, Franco decided not to rebuild it, leaving the ruined town as a symbol of the conflict. Instead, and against the wishes of its inhabitants, the dictator had a new town built nearby using slave labour: Republican prisoners.