The violent events of the 1937 May Days overwhelmed Barcelona when the division had been barely constituted. The 26th Division was then gathered in Barbastro in order to march over the city and restore order on behalf of the government. However, when the troops listened to the radio reports of the events by anarchist leader and Justice Minister García Oliver, they refused to intervene and decided to remain in Barbastro. Later in September the unit saw combat action in the Battle of Belchite, where its battle behaviour was clumsy, disorganized and inefficient at best. "General Kléber" commented about the 119th Mixed Brigade of the division that: 'It is totally useless' ("No sirve para nada...")