It was formed in August 1914 for the home defence of the United Kingdom from four existing mounted brigades of the Territorial Force, each of three regiments of Yeomanry.

It was converted to the 1st Cyclist Division in July 1916, and was broken up in November 1916 without being involved in active service.

The Mounted Division was formed on 5 August 1914, immediately after the outbreak of World War I, from four existing mounted brigades of the Territorial Force – Eastern, 1st South Midland, 2nd South Midland, and Notts.

Even as late as July 1915, some Royal Horse Artillery batteries were without guns, wagons or harnesses, machine guns were lacking and few of the men had fired a recruits' course of musketry.

All but 12 regiments were converted to cyclists:[4] the rest were dismounted, handed over their horses to the remount depots and were issued with bicycles.

The British units remained on the Western Front and the Indian elements were sent to Egypt.

[12] By an Egyptian Expeditionary Force GHQ Order of 12 April 1918, the mounted troops of the EEF were reorganised when the Indian Army units arrived in theatre.