
The Battle of Knocknanauss is fought on November 13, 1647, during the Irish Confederate Wars, part of the Wars of the Three Kingdoms, between Confederate Ireland’s Munster army and an English Parliamentarian army under Murrough O’Brien, 1st Earl of Inchiquin. The battle results in a crushing defeat for the Irish Confederates.
In the summer of 1647, Murrough O’Brien (later created the Earl of Inchiquin), commander of the English Parliamentarian forces in Cork, ravages and burns the Confederate territory in Munster. This causes severe food shortages and earns O’Brien the Irish nickname, Murchadh na d’Tóiteán (Murrough the Burner). In addition, Inchiquinn takes the Rock of Cashel, which is garrisoned by Confederate troops and rich in emotive religious symbolism. In the sack of the castle, O’Brien’s troops massacre the garrison and all the clergy they find there.
The Confederates’ Munster army is incapable of stopping O’Brien because of political infighting between officers who support a deal with the English Royalists and those who reject such a deal. Eventually, in reaction to the sack of Cashel and famine conditions, the Confederate Supreme Council replaces Donough MacCarthy, 2nd Viscount Muskerry, as commander of the Munster army with Theobald Taaffe, 1st Earl of Carlingford, and order him to bring O’Brien to battle.
Taaffe is an English Catholic and not an experienced soldier. Although he has an excellent contingent of veteran troops under Alasdair Mac Colla, most of his men are similarly inexperienced. Furthermore, the Irish troops are demoralised by the internal factionalism in their ranks and most of them have little loyalty to Taafe. O’Brien, on the other hand, has been commanding his force since 1642 and is well experienced in battle. His troops are a mixture of well trained Parliamentarian soldiers from England and British settlers who have been driven from their homes in the Irish Rebellion of 1641. The two armies meet at Knocknanuss near Mallow, approximately 29 kilometers north of Cork.
The battle that follows is essentially an uncoordinated rout of the Irish forces. Taaffe positions his men on either side of a hill, so that they cannot see one another. The result is that one wing of the Confederate army has no idea of what the other wing is doing. Mac Colla’s men charge the Parliamentarians opposite them putting them to flight and killing a large number of them. Thinking the battle is over, they then take to looting the enemy’s baggage train.
However, on the other wing, O’Brien’s cavalry has charged the raw Irish horsemen, causing them to run away. Despite Taaffe’s desperate attempt to rally them, the Irish infantry follow suit, many of them being cut down by the pursuing roundheads. The pursuit continues for miles and not only results in heavy casualties among the Irish, but also in the loss of most of their equipment and supplies. Inchiquin loses several senior officers, including the Judge-Advocate, Sir Robert Travers. Mac Colla and his men surrender when they realise what has happened but are subsequently killed by their captors. Around 3,000 Confederates die at Knocknanauss, and up to 1,000 English Parliamentarians. The carnage does not stop after the fighting is finished. The next day a couple of hundred Irish soldiers are found sheltering in a nearby wood. These are promptly put to the sword.
When combined with the Battle of Dungan‘s Hill in County Meath, the defeat leads to the collapse of the Confederate Catholic cause and forces them to make a deal with the English Royalists.