In June, 1690, King William arrived in Ireland to command the army in person, and the regiment was now called upon to serve under the eye of its sovereign. This circumstance is said to have given rise to a laudable feeling of emulation in all ranks of the army, and the troopers longed for an opportunity to distinguish themselves in presence of their King. The desired opportunity soon occurred; the King, advancing up to the banks of the _Boyne_, found the enemy in position on the opposite side of the river, and the troops prepared for battle. This regiment was with His Majesty on the evening preceding the battle, while reconnoitring the enemy's position, and was exposed to a cannonade, on which occasion the King was wounded in the shoulder, and the regiment had three men and nine horses killed. Early on the 1st of July, as the rays of morning-light shed their lustre on the camp, the English and Dutch troops appeared in motion, every man displaying a green branch in his hat; and soon the columns were seen advancing towards the Boyne, their glittering arms, waving plumes, and floating banners, exhibiting all the pomp of war: the French and Irish stood to their arms and prepared to defend their post. COY'S HORSE, forming part of the cavalry of the right wing, were in the column which forded the river near Slane Bridge; some opposition was made by a regiment of Irish dragoons, which was attacked, and its commanding officer and about 70 men killed. After passing the river, the troops advanced through large corn-fields, crossed several deep ditches, and overcoming every obstacle with an ardour which bespoke the valour and confidence which glowed in every breast, the enemy's left wing was dismayed and retreated towards Duleck. COY'S HORSE were amongst the squadrons which galloped forward in pursuit, and charging the Irish foot, cut them down with a great slaughter. While these events were transpiring on the right, King William passed the river with the main body of his forces: the enemy was overpowered at every point, and His Majesty stood triumphant on the field of battle. King James fled to Dublin, and afterwards to France, and was followed by the French troops; but the Irish Papists resolved to maintain his cause to the last extremity. COY'S HORSE advanced with King William to Dublin, and were afterwards with the army before _Limerick_, during the unsuccessful siege of that place, when His Majesty returned to England, the regiment went into quarters near Cork. [Sidenote: 1691]