The South Eastern Mounted Brigade was a formation of the Territorial Force of the British Army, organised in 1908.

[4] The brigade was mobilised on 4 August 1914 at the outbreak of the First World War and concentrated in the Canterbury area of Kent.

The Surrey Yeomanry (attached for training, pre-war) was detached in November 1914 and split up as divisional cavalry squadrons.

[5] The rest of the brigade remained in the Canterbury area (under Second Army of Central Force[6]) until September 1915,[3] the Field Ambulance detachment occupying the St Lawrence cricket ground.

In this period, the brigade consisted of the three yeomanry regiments, a signal troop and the field ambulance under the command of Br.-Gen. H.