After completing their training, the brigade was sent to the Huesca front. For the Zaragoza Offensive it stationed itself in Castellnou as a reserve and, on September 27, entered combat to support the XII International Brigade in the Villamayor sector. Later, Barceló was prosecuted for the shooting of a militia unit of the POUM, as was his successor, Bosch Montes. During the withdrawal from Aragón the brigade covered the Quinto sector and was overwhelmed by nationalist troops who attacked at this point, concentrating their remains in Montgay. Later the brigade took part in the fighting at the bridgehead of Balaguer, later moving to the sector of Artesa de Segre.[1] During the Battle of the Ebro, one of the unit's battalions participated in the combat.
On January 14, 1939, while the Catalonia Offensive was taking place, the brigade was positioned in a defensive line trying to defend Cervera, although it was lost the next day. It withdrew to Calaf and later to the Manresa-Vic area to continue the general withdrawal towards the French border.[1]
