The 1st Battalion, which was in Dublin at the outbreak of war in August 1914, was one of the first units to be moved to France where it became part of the 13th Infantry Brigade in the 5th Infantry Division. Among its first major engagements were the Battle of Mons on 23 August and Le Cateau three days later. In October the battalion made a heroic stand at Neuve Chapelle; being the only unit not to fall back. Out of 750 men, only 300 commanded by a Lieutenant and a Second Lieutenant survived. Apart from a brief period from December 1917 to April 1918, when it was moved with the 5th Division to Italy, the 1st Battalion was stationed on the Western Front for the duration of the war.