Militarily the Brigade achieved little; in its first action, near Ciempozuelos in February 1937, the Brigade was involved in a friendly fire incident with a Falangist unit while advancing to the front. Four brigaders and 13 Falangists were killed in the exchange of fire. Shortly after, at Titulcia in March 1937 the Brigade refused to advance after taking casualties and was withdrawn. Later, months of inactivity in a quiet sector sapped morale and saw an erosion of discipline; the unit was finally sent home in July 1937.