The Lincolns suffered heavy losses during the Battle of Jarama. On February 27, 1937 the unit lost two-thirds of its strength including their commander, Robert Hale Merriman (who was badly wounded), in a futile assault on Nationalist positions. The battalion remained in the lines and was slowly rebuilt while maintaining its front-line trenches. The unit was pulled out of the lines for a brief rest before the offensive at Brunete.