For a large proportion of the First World War, the two Irish Guards' battalions campaigned together on the Western Front with the Guards Division.
1st Battalion.
Transferred to the 1st Guards Brigade (the renamed 4th Guards Brigade) in the Guards Division from 2nd Division during August 1915.
Mons, the Marne, the Aisne, 1st Ypres: August 1914 to November 1914.
Festubert, Loos: May 1915 to October 1915.
Somme: August 1916 to September 1916.
Ypres sector: 1917.
German Spring offensive: March 1918 to April 1918.
Final offensive: August 1918 to November 1918.
2nd Battalion.
Joined the 2nd Guards Brigade in the Guards Division during August 1915
The 2nd Battalion left to join the 4th Guards Brigade, who were in 31st Division, during February 1918.
Loos: September 1915 to October 1915.
Ypres sector: 1916.
Somme: September 1916.
Third Ypres: 1917.
German Spring offensive: March 1918 to April 1918.
Final offensive: August 1918 to November 1918,