It saw action during the Irish Rebellion of 1798 and served in home defence through the major wars of the 19th Century, It later became a battalion of the Royal Inniskilling Fusiliers but was disbanded in 1908.

During the 18th Century there were various Volunteer Associations and unofficial militia units controlled by the landowners, concerned mainly with internal security.

While most of the Regular Army was fighting overseas, the coasts of England and Wales were defended by the embodied Militia, but Ireland had no equivalent force.

The new Act was based on existing English precedents, with the men conscripted by ballot to fill county quotas (paid substitutes were permitted) and the officers having to meet certain property qualifications.

[1][2] County Donegal was given a quota of 560 men to find, in ten companies, and the order for embodiment was issued on 23 April 1793, with William Burton Conyngham, former Lieutenant-Colonel in the 12th Dragoons appointed as Colonel of the regiment.

Many of those liable to serve formed insurance societies to pay bounties to attract volunteer substitutes for the balloted men.

[3][4][5][6][7][8] The French Revolutionary and Napoleonic Wars saw the British and Irish militia embodied for a whole generation, becoming regiments of full-time professional soldiers (though restricted to service in Britain or Ireland respectively), which the regular army increasingly saw as a prime source of recruits.

They served in coast defences, manned garrisons, guarded prisoners of war, and carried out internal security duties.

[10] The regiment marched to Birr, where it was inspected again on 11 August 1794 and by the end of the month it was stationed at Athlone, with two companies detached to Castlerea and one to Roscommon.

A large French expeditionary force appeared in Bantry Bay on 21 December and troops from all over Ireland were marched towards the threatened area.

The invasion was called off on 29 December, and the troop concentration was dispersed in early 1797, the Donegal Militia returning to Loughlinstown Camp.

On 30 May a company of the Royal Meath Militia escorting a train of artillery to Wexford was ambushed by the United Irishmen and cut up at the First Action at Forth Mountain (or Battle of Three Rocks).

[7] With the diminishing threat of invasion after 1799, the strength of the militia could be reduced, and the surplus men were encouraged to volunteer for regiments of the line.

The Donegal men were inspected and paid off at Lifford on 12 May, leaving only the permanent staff of non-commissioned officers (NCOs) and drummers under the regimental adjutant.

The Donegal Militia was re-embodied by Col Viscount Clements at Lifford on 15 March, and Britain declared war on France on 18 May 1803.

With the end of the war most Irish Militia regiments returned to their home counties to be disembodied, the Donegals being at Ballyshannon by July 1814.

However, some regiments, including the Donegal, had not completed disembodiment by the time the militia was called out again in May 1815 after Napoleon's escape from Elba.

For the Donegal Militia this was in Sub-District No 64 (Counties of Londonderry, Donegal, Tyrone and Fermanagh in Belfast District of Irish Command:[40] Although often referred to as brigades, the sub-districts were purely administrative organisations, but in a continuation of the Cardwell Reforms a mobilisation scheme began to appear in the Army List from December 1875.

[3][4][30][40] After the Second Boer War broke out in October 1899 an expeditionary force was sent to South Africa and the militia reserve was called out to reinforce it.

There were moves to reform the Auxiliary Forces (Militia, Yeomanry and Volunteers) to take their place in the six Army Corps proposed by the Secretary of State for War, St John Brodrick.

Lieutenant-colonels of the regiment included: The following served as Honorary Colonel of the battalion: The Donegal Militia wore a red coat, with facings that are variously recorded as black in 1850[7] or white from 1860.

[25][40] The regiment's badge was the Prince of Wales's insignia of three feathers emerging from a crown with the motto 'Ich Dien', together with a scroll inscribed 'DONEGAL MILITIA' underneath.

[40][47] On the outbreak of the French Revolutionary War the English counties had drawn lots to determine the relative precedence of their militia regiments.