Brigade, XV IB. The other battalions were the US Lincoln Battalion, the crack Balkan Dimitrov Battalion, and the Franco-Belgian Sixth February Battalion. Jarama, 1937 In February 1937, the battalion fought at the Battle of Jarama. In a single day's bloody fighting on 12 February against Moors from Francisco Franco's Army of Africa, the British Battalion suffered 275 casualties in No.1, No.3, and No.4 companies – leaving 125 rifleman fit for duty. On the second day of fighting, the machine gun company was surrounded by Spanish Nationalist troops and many of its members were captured. Battalion commander Tom Wintringham was injured, and Jock Cunningham took command of the battalion's 140 survivors. The battalion remained in the trenches at Jarama until 17 June 1937. Brunete, 1937 Reinforced by new recruits and strengthened by returnees from hospital, the British Battalion mustered 331 brigaders at the Battle of Brunete. On 6 July, XV IB occupied the villages of Romanillos and Boadilla del Monte, and by midnight captured the village of Villanueva de la Cañada. (It was here that Alex McDade who wrote the song, Valley of Jarama, commonly heard at Brigade meetings, was killed in action.) The following day the British were ordered to advance on Mosquito Ridge, a piece of high ground which overlooked the battalion's original objectives. As they left Villanueva de la Cañada they were bombed by Junkers aircraft from the Condor Legion and shelled by Nationalist artillery. The two-hour barrage and devastating heat caused heavy casualties and prevented the battalion reaching Mosquito Ridge before Franco's army rushed reinforcements to defend the position. Only 42 members of the battalion were left fit for service, and the battalion was withdrawn into a reserve position. Aragon, 1937 In mid-August, the Republican 35th Division, which included XV IB, was moved to Aragon. The focus of the Aragon campaign was to draw-off Nationalist attacks on Santander and to capture the strategic city of Zaragoza. On 25 August the battalion took part in street fighting to capture the Nationalist strongpoint at Quinto, where Wintringham, now head of the Officer's School and attached to the American Lincoln and Canadian MacKenzie/Papineau battalions, was shot again, this time badly and injured out of the war. On 25 August the battalion attacked a strong Francoist position at Purburrel Hill, and was repelled by intense rifle and machine gun fire. The following day another assault was made on the hill, supported