In February, 1690, the regiment was stationed at Belturbet, with the Inniskilling horse and dragoons (now sixth), and the Queen Dowager's foot (now second); and information having been received that the enemy was assembling a body of troops at _Cavan_, Colonel Wolseley left Belturbet on the night of the 10th of February, with three hundred horse and dragoons, and seven hundred foot of the second and TWELFTH regiments, to surprise the enemy in his quarters. Encountering difficulties on the march, the day had dawned before the Colonel came in sight of Cavan, when he was surprised at discovering four thousand Irish soldiers, commanded by the Duke of Berwick, formed on a rising ground to oppose him. The Colonel had only one thousand tired soldiers[6] to attack four thousand fresh opponents with, but trusting to the valour of his men, he sent the cavalry forward to commence the action. The enemy's cavalry drove back the Inniskilling dragoons; but a volley from the English musketeers, brought down ten Irish horsemen, and the survivors fell back. Wolseley's infantry formed line and advanced: arriving within pistol-shot of their opponents, they opened a sharp fire with good effect, and after a few volleys, drew their swords to charge, but on the smoke clearing, they discovered that their opponents had fled. Pursuing the fugitives, they entered the town, and finding stores of necessaries and provisions, they halted to possess themselves of the booty; when the Irish rallied and resumed the fight, but were repulsed by the reserve. After the action the troops returned to Belturbet. A numerous body of recruits from England replaced the losses of the regiment, and in June it brought five hundred musketeers, one hundred and sixty pikemen, and sixty grenadiers into the field, to serve under King William III., who commanded the army in Ireland in person. The TWELFTH regiment, commanded by Colonel Brewer, had the honour of taking part at the forcing of the passage of the _Boyne_ on the 1st of July: it formed part of the main body under King William III., and after fording the river, engaged King James's army, and contributed to the gaining of a decisive victory. After the loss of this battle, King James fled to France; but the Irish Roman Catholics, aided by the French troops, adhered to his interest. From the field of battle the regiment accompanied King William to Dublin; it afterwards proceeded to Limerick, but on arriving at Carrick-on-Suir, it was detached, under Major General Kirke, to besiege _Waterford_: the garrison of this place surrendered without waiting for an attack. King William afterwards besieged _Limerick_; but King James's soldiers made a more resolute defence than appears to have been expected, and His Majesty was induced to raise the siege, and send the troops into quarters.