When Wellington organized his troops into numbered divisions for the Peninsular War, the component brigades were named for the commanding officer.

[a] For the Hundred Days Campaign, he numbered his British infantry brigades in a single sequence, 1st to 10th.

[14] At the outbreak of the First World War in August 1914, the 7th Brigade was a regular army formation stationed at Tidworth and assigned to the 3rd Division.

Other than a brief period when it was reorganized in England in 1918,[16] the brigade served with the 3rd and 25th Divisions on the Western Front throughout the war.

[20] Once there, it was extensively reorganized on 26 October:[18] On 12 January 1916, the brigade formed the 7th Machine Gun Company and was joined by the 7th Trench Mortar Battery on 18 June 1916.

[28] Due to a shortage of manpower, all British[c] divisions on the Western Front were reduced from a 12-battalion to a 9-battalion basis in February 1918.

It was once again moved south to a quite part of the line where it was attacked for the third time in the Battle of the Aisne (27 May – 6 June).

[16] Due to losses sustained, the division was withdrawn from the line and the brigades were reduced to cadre.

[16] Units left behind in France (artillery, engineers, signals, pioneers, machine gunners, etc.)

It was stationed at Pirbright Camp with the following units under command: The brigade, commanded by Brigadier John Whitaker, moved to France with the rest of the 3rd Division on 30 September 1939 as part of the British Expeditionary Force (BEF) and remained there, serving alongside the French Army, until May 1940.

It first saw action against the German Army's offensive in Belgium and France, notably on the Ypres-Comines Canal (26 – 28 May 1940) before being evacuated from Dunkirk to the United Kingdom by 1 June.