First raised as a full regiment 1684. Originally a largely Catholic regiment under James II but purged of Catholics under William III.
Service (for fuller details see Kronoskaf WSS (from which the details below were extracted) here: https://kronoskaf.com/wss/index.php?title=Royal_Regiment_of_Ireland ):
1689 Siege and capture of Carrickfergus
1690 Battle of the Boyne; capture of Castle-Connell; siege and capture of Limerick; relief of Birr.
1691 Siege and capture of Ballymore; siege and capture of Athlone; battle of Aughrim; capture of Galway; siege of Limerick.
1692 Nine Years War: capture of Furnes and Dixmude.
1693 Served as marines.
1694 Siege of Huy.
1695 Siege of Namur; storm of the citadel of Namur (with heavy losses). Renamed "The Royal Regiment of Foot of Ireland", later changed to "Royal Irish Regiment."
1697 Sent to Ireland where it remained to 1700. It consisted of one battalion of ten companies with 34 officers and 411 men.
Colonel commandants during the WSS were; from 1692 Frederick Hamilton; from 1705 Richard Ingoldsby; 1712-1717 Richard Stearne.
Service in the War of the Spanish Succession:
1702 Covered the siege of Kaiserswerth; siege of Venloo; siege of Roermond; capture of the citadel of Liège
1703 Siege and capture of Huy; siege of Limbourg
1704 Battle of the Schellenberg where 1 sergeant and 11 rank and file were killed; Captain Lea, Ensigns Gilman, Walsh, and Pensant, 3 sergeants and 32 rank and file wounded; siege of Ingolstadt; battle of Blenheim Captains Brown, Rolleston, and Vaughan, Ensign Moyle, 5 sergeants, and 52 rank and file killed; Major Kane, Captains Lepenitor and Hussey, Lieutenants Smith, Roberts, Blakeney, and Harvey, Ensign Trips, 9 sergeants and 87 and file wounded; siege of Landau.
1705 Passage of the Lines near Helixem and Neer-Hespen (but not in action there)
1706 Battle of Ramillies; siege and capture of the fortress of Menin; siege of Ath.
1708 Battle of Oudenarde where it had 1 lieutenant and 8 men killed; and 12 men wounded; siege of Lille where it lost 2 captains and 3 subalterns killed; its major and several other officers wounded; and 200 NCOs and soldiers killed or wounded.
1709 Siege of Tournai - storming the Ravelin and Half-Moon followed by the siege of the citadel; battle of Malplaquet; siege of Mons.
1710 Sieges of Douai and Béthune; siege of Aire with 3 officers killed and 5 wounded; also around 80 soldiers killed or wounded.
1711Passing the French Lines at Arleux; siege of Bouchain where it lost 4 officers wounded and around 40 men killed or wounded.
1712-1713 Winter; a serious mutiny in the regiment incited by one man; suppressed and 10 ringleaders executed.
And the uniform for the hat companies was probably like this in the WSS (the grenadiers wore an elaborate mitre cap):
