The Gloucester and Worcester Brigade was first raised under the Haldane Reforms in 1908 as part of the Territorial Force, which was formed by amalgamating the Volunteer Force and the Yeomanry, consisting of the 4th (City of Bristol) and 6th Volunteer battalions of the Gloucestershire Regiment and the 7th and 8th battalions of the Worcestershire Regiment.

[1] In March 1915 the division was warned to prepare for overseas service on the Western Front to reinforce the Regulars of the British Expeditionary Force.

The brigade served with the 48th Division throughout the war in the trenches of the Western Front in the Somme offensive of July 1916, pursuing the German Army in the retreat to the Hindenburg Line in March 1917 and later in the Third Battle of Ypres.

This was due to BEF policy and the intention was to strengthen the Territorial divisions and give them vital experience.

[9] After returning to the United Kingdom, the brigade, with the rest of 48th Division, spent the next few years on home defence, absorbing replacements after heavy casualties in France and training to repel a German invasion, which never arrived.