To officers and soldiers imbued with a laudable _esprit de corps_, the particulars relating to the origin and services of their regiment are of intense interest, and the circumstances which gave rise to the formation of their corps are of themselves an era. To encourage such feelings is one of the objects of the present undertaking, and, although the general reader may think the narrative tedious, the officers and men of the ROYAL IRISH DRAGOON GUARDS will feel gratified at learning by whom, and where, each troop, of which their regiment was originally composed, was raised. This information has been procured from public documents, in which it is recorded that, in the midst of the hostile preparations which the Duke of Monmouth's rebellion occasioned in every part of the kingdom, a troop of horse was raised by JAMES EARL OF ARRAN, eldest son of William Duke of Hamilton, a nobleman distinguished alike for loyalty and attachment to the Protestant religion; a second troop was raised, in the vicinity of London, by Captain John Parker, Lieutenant of the Horse Grenadier Guards attached to the King's Own troop of Life Guards (now First Regiment of Life Guards); a third at Lichfield, by William Baggott, Esq.; a fourth at Grantham, by Thomas Harrington, Esq.; a fifth at Durham, by John Fetherstonhalgh, Esq.; and the sixth at Morpeth, by William Ogle, Esq.; and that, after the decisive battle of Sedgemoor had destroyed the hopes of the invader, these six troops were ordered to march to the south of England, and were incorporated into a regiment of CUIRASSIERS, which is now the FOURTH OR ROYAL IRISH REGIMENT OF DRAGOON GUARDS. The Colonelcy was conferred on the EARL OF ARRAN, by commission, dated the 28th of July, 1685; the Lieutenant-Colonelcy on Captain Charles Nedby,[7] from the Queen's regiment of horse; and the commission of Major on Captain John Parker. At the formation of this regiment it ranked as SIXTH HORSE, but was distinguished by the name of its Colonel, the practice of using numerical titles not having been introduced into the British army until the reign of King George II. This corps being composed of the sons of substantial yeomen and tradesmen, who provided their own horses, it was held in high estimation in the country, and the men were placed on a rate of pay (2_s._ 6_d._ per day) which gave them a respectable station in society. Few nations in Europe possessed a body of troops which could vie with the English horse in all the qualities of good soldiers, and, in the reigns of King William III. and Queen Anne, this _arme_ acquired a celebrity for gallantry and good conduct; and these qualities, whether evinced by bravery in the field, or by steadiness and temperate behaviour when their services have been required on home duties, have proved their usefulness, and have rendered them valuable corps during succeeding reigns.