Battle of Albert. 1-13 Jul 1916, including the capture of Montauban, Mametz, Fricourt, Contalmaison and La Boisselle.

Battle of Messines. 7-14 Jun 1917, including the capture of Wytschaete.
Battle of Langemarck. 16-18 Aug 1917.
The tank attack. 20-21 Nov 1917.
Capture of Bourlon Wood. 23-28 Nov 1917.
German counter attacks. 30 Nov-3 Dec 1917.

Battle of St. Quentin. 21-23 Mar 1918.
Actions of the Somme crossings. 24-25 Mar 1918.
Battle of Rosieres. 26-27 Mar 1918.
Battle of Messines. 10-11 Apr 1918.
Battle of Bailleul. 13-15 Apr 1918, including the defence of Neuve Eglise.
First Battle of Kemmel. 17-19 Apr 1918.
Advance in Flanders. 18 Aug-6 Sep 1918.
Battle of Ypres. 28 Sep-2 Oct 1918.
Battle of Courtrai. 14-19 Oct 1918.
Action of Ooteghern. 25 Oct 1918.

12th Brigade. (Served with the Division from 05 Nov 1915 until 03 Feb 1916).

1st Bn King’s Own. 05 Nov 1915 - 03 Feb 1916. To the 4th Division.
2nd Bn Lancashire Fusiliers. 05 Nov 1915 - 03 Feb 1916. To the 4th Division.
2nd Bn Duke of Wellington’s Regt. 14 Jan 1916 - 03 Feb 1916. To the 4th Division.
1/5th Bn South Lancashire Regt. 05 Nov 1915 - 06 Jan 1916. To the 55th Division.
1/2nd Bn Monmouthshire Regt. 05 Nov 1915 - 30 Jan 1916. To the L of C Troops.

107th Brigade. (1st Ulster Brigade.) (Exchanged with the 12th Brigade, 4th Division from 05 Nov 1915 until 03 Feb 1916. All the Battalions serving with the Brigade at that time went to the 4th Division).

1st Bn Royal Irish Rifles. 04 Feb 1918 - 11 Nov 1918.
2nd Bn Royal Irish Rifles. 08 Feb 1918 - 11 Nov 1918.
8th Bn Royal Irish Rifles. Sep 1914 - 29 Aug 1917. Amalgamated with the 9th Bn to form the 8/9th Bn.
8/9th Bn Royal Irish Rifles. 29 Aug 1917 - 07 Feb 1918. Disbanded.
9th Bn Royal Irish Rifles. Sep 1914 - 29 Aug 1917. Amalgamated with the 8th Bn to form the 8/9th Bn.
10th Bn Royal Irish Rifles. Sep 1914 - 20 Feb 1918. Disbanded, personnel to the 21st Entrenching Bn.
15th Bn Royal Irish Rifles. Sep 1914 - 11 Nov 1918.
1st Bn Royal Irish Fusiliers. 24 Aug 1917 - 08 Feb 1918. To the 108th Brigade.

108th Brigade. (2nd Ulster Brigade).

2nd Bn Royal Irish Rifles. 14 Nov 1917 - 08 Feb 1918. To the 107th Brigade.
7th Bn Royal Irish Rifles. 15 Oct 1917 - 14 Nov 1917. Absorbed by the 2nd Bn.
11th Bn Royal Irish Rifles. Sep 1914 - 13 Nov 1917. Amalgamated with the 13th Bn to form the 11/13th Bn.
11/13th Bn Royal Irish Rifles. 13 Nov 1917 - 19 Feb 1918. Disbanded, personnel to the 22nd Entrenching Bn.
12th Bn Royal Irish Rifles. Nov 1914 - 11 Nov 1918.
13th Bn Royal Irish Rifles. Sep 1914 - 13 Nov 1917. Amalgamated with the 11th Bn to form the 11/13th Bn.
1st Bn Royal Irish Fusiliers. 08 Feb 1918 - 11 Nov 1918.
9th Bn Royal Irish Fusiliers. Sep 1914 - 11 Nov 1918.

109th Brigade. (3rd Ulster Brigade).

1st Bn Royal Inniskilling Fusiliers. 05 Feb 1918 - 11 Nov 1918.
2nd Bn Royal Inniskilling Fusiliers. 03 Feb 1918 - 11 Nov 1918.
9th Bn Royal Inniskilling Fusiliers. Sep 1914 - 11 Nov 1918.
10th Bn Royal Inniskilling Fusiliers. Sep 1914 - 21 Jan 1918. Disbanded, personnel to the 2nd Bn.
11th Bn Royal Inniskilling Fusiliers. Sep 1914 - 21 Feb 1918. Disbanded, personnel to the 9th Bn.
2nd Bn Essex Regt. 05 Nov 1915 - 03 Feb 1916. To the 4th Division.
14th Bn Royal Irish Rifles. Sep 1914 - 18 Feb 1918. Disbanded.

Pioneers.

16th Bn Royal Irish Rifles. 06 Jan 1915 - 11 Nov 1918.

Attached Troops.

1st Bn Royal Irish Fusiliers. 03 Aug 1917 - 24 Aug 1917. To the 107th Brigade.

1st City of London Brigade. Left the Division Dec 1915 and joined the 38th Division.

1st City of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
2nd City of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
3rd City of London Bty. Sep 1915 - 11Dec 1915. To the 38th Division.

2nd London Brigade. Left the Division Dec 1915 and joined the 38th Division.

4th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
5th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
6th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.

3rd London Brigade. Left the Division Dec 1915 and joined the 38th Division.

7th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
8th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.
9th County of London Bty. Sep 1915 - 11 Dec 1915. To the 38th Division.

4th London (Howitzer) Brigade. Left the Division Dec 1915 and joined the 38th Division.

10th County of London (Howitzer) Bty. Sep 1915 - 12 Dec 1915. To the 38th Division.
11th County of London (Howitzer) Bty. Sep 1915 - 12 Dec 1915. To the 38th Division.