The addition of a fourth Army to the British Expeditionary Force took place on 5 February 1916. It was initially placed under the command of General Sir Henry Rawlinson. Fourth Army remained on the Western Front throughout the rest of the war.
- 5 February 1916 : Tilques
- 24 February 1916: Querrieu
- 15 April 1917: Villers Carbonnel
- 5 July 1917: Malo-les-Bains
- 25 October 1917 : Rosendael (Dunkirk)
- 5 November 1917 : Dury
- 9 November 1917: staff and HQ of Fourth Army takes over from Second Army at Cassel. On 20 December 1917 what had been Second Army was renamed as Fourth Army. On 13 March 1918 the units under Fourth Army were placed under command of the reconstituted Second Army and four days later what had been Fourth Army was renamed as Second Army.
- 22 March 1918 : Querrieu
- 25 March 1918 : Picquigny-sur-Somme
- 27 March 1918 : Abbeville. Next day, Fourth Army took over command of Fifth Army. The latter ceased to exist on 2 April 1918.
- 30 March 1918 : Auxi-le-Chateau
- 31 March 1918 : Flixecourt
- 2 April 1918 : Dury
- 5 April 1918 : Flixecourt
- 30 August 1918 : Bertangles
- 25 September 1918 : Eterpigny
- 14 October 1918 : Montigny Farm (Roisel, HQ located in a train)
- 3 November 1918 : Honnechy (in a train)
- 16 November 1918 : Avesnes
- 30 November 1918 : Ham-sur-Heure
- 10 December 1918 : Namur
- 5 February 1916 : General Sir Henry Rawlinson
- 21 February 1918 : General Sir William Birdwood (temporary appointment. Rawlinson had been appointed as Permanent Military Representative to the British delegation at the Supreme War Council)
- 28 March 191 8: General Sir Henry Rawlinson
- The Battles of the Somme 1916 (July-November 1916)
- Pursuit of the German retreat to the Hindenburg Line (March-April 1917)
- The Battle of Amiens (August 1918)
- The Second Battles of the Somme 1918 (August-September 1918)
- The Battles of the Hindenburg Line (September-October 1918)
- The final advance in Picardy (October-November 1918)
Fourth Army Headquarters established in a camouflaged railway train at Montigny Farm, near Peronne in France, October 1918. IWM image E(AUS)3929, with my thanks.