War brought a need for more soldiers and expansion in the Army.  Among the new regiments raised to fight France were many Irish ones including the 83rd, 87th and 89th Regiment.  The 87th and 89th were later to become The Royal Irish Fusiliers.  In England another regiment, at first known as Major-General Cornelius Cuyler's Shropshire Volunteers, was raised in November 1793: this later came to Ireland and became the 86th Foot, eventually to join with the 83rd as The Royal Irish Rifles.

For almost twenty years Britain was at war with France, at first with the revolutionary government and then with Napoleon.  Irish regiments distinguished themselves in many campaigns across the globe as this war was not confined to Europe.  Three battalions of Inniskillings fought in Flanders, Egypt, Italy, the Peninsula and North America gaining many new battle honours for the Regiment.  One of those honours was St Lucia where, to mark the gallantry of the Inniskillings in the assault on Morne Fortune, the force commander, General Abercromby, ordered that the French should lay down their arms to the 27th only.

French Revolutionary and Napoleonic Wars
In other theatres too our Regiments had distinguished themselves.  Two battalions of the 27th, as well as the 86th and 89th, served in Egypt in 1801 and all were permitted to bear the Sphinx, superscripted Egypt, on their colours.  In 1810 the 86th were part of the force which captured the island of Bourbon.  Corporal William Hall of the 86th climbed the flagstaff under heavy fire to fly the Regiment's King's Colour; the title The Royal County Down was granted to the 86th in recognition of this action.  Another island taken by a British expeditionary force was Mauritius where the force included the 1st/87th and 1st/89th.

Barrosa
Other distinctions were gained by the 27th, 83rd, 86th, 87th and 89th.  At Barrosa on 5 March 1811 Sergeant Patrick Masterson of the 2nd/87th (Prince of Wales's Irish) Regiment captured the first French eagle to be taken in battle.  The regiment was subsequently restyled The Prince of Wales's Own Irish Regiment with the eagle as a badge of honour.  That eagle is worn today on officers' cross belts.  On that day also the regimental motto was gained as the Irishmen charged to the old Gaelic battle-cry Faugh A Ballagh!  Clear the Way!  The 2nd/87th played a major part in the defence of Tarifa some nine months later while the 2nd/83rd fought with distinction in the Battalion of Fuentes d'Onor (known to the soldiers as the Fountains of Horror).

Killaloe
The distinctive 'yell' given during the playing of today's Regimental March, 'Killaloe' has its origins in the Peninsular War.  The drums of the Connaught Rangers would always pause during the playing of 'Brian Boru's March' for the 'yell' and Irish soldiers charging into battle terrified their French opponents with their wild Gaelic battle-cries, just at Masterson and his comrades had done at Barrosa.

1812
In 1812 the 2nd/83rd fought at Cuidad Rodrigo, Badajoz and Salamanca.  At Vittoria in 1813 the 3rd/27th, 2nd/83rd and 2nd/87th were all present, the latter two brigades together in Picton's Division.  It was a sergeant of the 2nd/87th who "captured" Marshal Jourdan's baton which became the model for the baton of a British Field Marshal.  After Vittoria the Allies were able to invade France; all three battalions were at the battles of Nivelle and Orthes and then at Toulouse, the war's last battle.