Under threat of invasion by the French Revolutionary government from 1793, and with insufficient military forces to repulse such an attack, the British government under William Pitt the Younger decided in 1794 to increase the Militia and to form corps of volunteers for the defence of the country.

[4] Col. Henry II Beavis (1736–1813), of Yeotown in the parish of Goodleigh, North Devon, was appointed on 5 July 1803 by the King as Lieutenant-Colonel Commandant (of 441 men) of the "Barnstaple Volunteer Infantry".

He died on 7 December 1813, and his small mural monument survives in Pilton Church inscribed as follows: Despite the end of the Napoleonic Wars in 1815, the Yeomanry was retained by the government "for Military Service in aid of the Civil Power"[6] in the absence of organised police forces.

Members of the Regiment were mustered and patrolled the town all night; several rioters were arrested and escorted to Exeter.

[4] Due to the string of defeats during Black Week in December 1899, the British government realized they were going to need more troops than just the regular army, thus issuing a Royal Warrant on 24 December 1899 to allow volunteer forces to serve in the Second Boer War.

The Royal Warrant asked standing Yeomanry regiments to provide service companies of approximately 115 men each.

[12] On 17 April 1901, the regiment was renamed as the Royal North Devonshire Imperial Yeomanry and reorganised in four squadrons and a machine gun section.

On 1 April 1908, the regiment was renamed for the final time as the Royal North Devon Yeomanry and transferred to the Territorial Force, trained and equipped as hussars.

[16] At the outbreak of the First World War, the regiment was part of the 2nd South Western Mounted Brigade.

[17] Still with the 2nd South Western Mounted Brigade, in September 1915 the regiment left Colchester for Liverpool.

The regiment landed in Gallipoli on 9 October and was attached to the 11th (Northern) Division[18] (digging trenches).

In September 1915 it moved to Colchester, taking over the horses of the newly dismounted 1st Line regiment.

In March 1917 it resumed its identity as 2/1st Royal North Devon Yeomanry, still with the 2nd Cyclist Brigade, at Melton Constable before moving to East Dereham later in 1917.

Following the experience of the war, it was decided that only the fourteen most senior yeomanry regiments would be retained as horsed cavalry,[34] with the rest being transferred to other roles.