1650: The Siege of Clonmel
After the fall of Kilkenny in March 1650, the Council of State in London urgently wanted Oliver Cromwell to return from Ireland to deal with the growing threat of a Royalist invasion from Scotland. Cromwell, however, was determined to secure Leinster and Munster before leaving Ireland. During April 1650, he was based at Ormond's manor house at Carrick-on-Suir, from where he directed military operations. The main Royalist strongholds remaining in southern Munster were Clonmel and Waterford but before moving against them, Cromwell sent out columns to reduce remaining Royalist outposts around Kilkenny. Cromwell's troops ruthlessly put to the sword officers of any garrison taken by storm after refusing to surrender. Garrisons that surrendered were allowed to march away, leaving their weapons behind. The Earl of Castlehaven with a force of 3,000 men made a half-hearted attempt to disrupt English operations at Carlow, but lacking infantry to fight a pitched battle he withdrew into Connacht.
The defeat of Lord Inchiquin in March effectively ended Protestant support for Ormond's Royalist-Confederate coalition. The Catholic clergy and Old English nobles demanded that Ormond disband the last Protestant units so that they would no longer be quartered on the Catholic population. Cromwell was eager to take advantage of the situation and offered a treaty with the Protestant Royalists independently of Ormond and Inchiquin. On 24 April, Cromwell met a delegation headed by Michael Boyle, the Protestant Dean of Cloyne, at Cashel. After two days of negotiation, a treaty was signed under which the Protestant forces in Ireland undertook not to act against the interests of the English Commonwealth, while Cromwell guaranteed the security of their lives and property. The treaty was accepted by most Protestant Royalists still in arms in Leinster and Munster, and also by the Ulster Scots and the Lagan Army. As the King's Lord-Lieutenant, Ormond remained the nominal commander of forces in Ireland, but in practice he had little influence over the Irish Catholics who remained in arms.
Having secured the surrender of the Protestant Royalists, Cromwell marched to join Parliamentarian forces besieging Clonmel, which was defended by Hugh Dubh O'Neill, a nephew of Owen Rowe O'Neill. Hugh was a veteran of the Spanish service and a major-general in the Confederate army of Ulster. He arrived to take command of the Clonmel garrison in December 1649 with 1,200 Ulstermen. Although his forces were steadily reduced by plague, the garrison was reinforced by Irish troops ejected from Cashel and Kilkenny during February and March 1650.
Clonmel is situated on the north bank of the River Suir twelve miles west of Carrick. It was protected on its western, northern and eastern sides by a circuit of walls over twenty feet high and six feet thick. Its southern side was protected by the Suir and minor defensive works. The walls had additional earthwork reinforcement making them difficult to breach with artillery, and a deep ditch ran around the outside as a defence against mining. The town was loosely blockaded by Cromwell's forces in February 1650 and food supplies were running low. Despite the shortages and the ravages of the plague, however, Hugh O'Neill maintained firm discipline over his troops which encouraged the co-operation of the mayor and townsmen of Clonmel. O'Neill believed that Ormond was raising an army in Ulster to challenge Cromwell and was therefore determined to defend Clonmel for as long as possible.
Cromwell arrived to take charge of the siege on 27 April 1650 with an additional force of 8,000 infantry, 600 cavalry and twelve field guns. He was anxious to conclude operations in Munster before returning to England and planned to take Clonmel by storm rather than relying upon the lengthier process of starving the garrison into submission. In early May, Cromwell's gunners began bombarding Clonmel's northern wall, but the field guns he had brought with him were not powerful enough to make a breach large enough to allow a massed assault. Cromwell therefore had to wait for heavy siege artillery to be hauled overland to Clonmel. Meanwhile, O'Neill conducted an aggressive defence, mounting frequent raids on the English lines to disrupt work parties constructing the siege works.
While the siege was in progress, David Roche, the Irish commander in western Munster, gathered a force of 2,000 men in County Kerry to march for the relief of Clonmel. Around 8 May, Roche's army arrived at Macroom and advanced towards Cork. However, Lord Broghill was active in the region with 1,200 infantry and 800 cavalry. Roche fell back towards Macroom as Broghill's forces advanced towards him. Rather than risk allowing the Irish to escape, Broghill pursued them with his cavalry. On 10 May, the fast-moving English calvary caught up with Roche's troops near Macroom and attacked immediately. The Irish had no time to form defensive lines and were soon routed. Up to 600 Irishmen were killed in the attack; the rest escaped into the hills and bogs where the English cavalry could not follow.
The following day, Broghill advanced to the nearby Irish outpost at Carrigadrohid Castle taking along the captive Bishop of Ross, Boetius MacEgan, as a hostage. Broghill threatened to hang the bishop if the garrison did not surrender. When MacEgan bravely told the garrison to defy Broghill he was tortured and hanged in view of the castle. Broghill then offered lenient terms, which were accepted by the garrison commander, who was allowed to march away with his men.
By 16 May, heavy siege guns had arrived at Clonmel and batteries were established. The guns were situated 200 yards from the North Gate on an elevated position at Gallows Hill. Cromwell was limited to bombarding the northern wall because the ground to the east and west was too boggy to support the weight of his artillery. Unlike the successful assaults on Drogheda, Wexford and Kilkenny, only a single breach was made at Clonmel, which allowed Hugh O'Neill to concentrate the defenders at the obvious point of attack.
The heavy guns opened fire on 16 May and had opened a breach wide enough to allow an assault by the following morning. Cromwell's plan was to send infantry into the breach to fight their way into the town and capture the North Gate. Cromwell and his cavalry would be waiting to charge in as soon as the gate was opened. Unknown to Cromwell, however, O'Neill had strengthened the defences immediately behind the point where the English gunners were battering the wall. A V-shaped inner fortification of earth and timber had been constructed around the weak point. Its walls were about six feet high and lined with musketeers. The walls converged at a point about eighty yards from the breach where two cannon were placed. When the English soldiers stormed through the breach, they found themselves in an area enclosed by O'Neill's fortification with no shelter from the Irish musketeers and cannon. Unable to advance further and trapped by the weight of numbers of the troops still coming through the breach, the Parliamentarians were cut down by musket fire and chain shot fired at point-blank range. Up to 1,000 infantrymen were killed before the survivors retreated from the breach.
Cromwell tried to rally his troops for another assault, but the infantry refused to enter the breach a second time. Instead they called upon Cromwell to send in the cavalry, who were protected by iron helmets and body armour (and were better-paid than the infantry). Regimental cavalry commanders immediately volunteered to lead the assault. At around 3 p.m., Colonels Culme and Sankey led a column of dismounted cavalrymen in a second assault on the fatal breach. The Irish defenders were quickly driven from the main breach and back to the inner fortification. Fierce hand-to hand fighting continued for three hours but the English were unable to penetrate the Irish defence. They finally retreated after most of their officers and hundreds more troopers had been killed.
Estimates of the number of English soldiers killed at the assault on Clonmel vary between 1,500 and 2,500 men. It was the first major defeat inflicted on the New Model Army and was by far the greatest loss of life it had sustained in a single action. Cromwell could not afford to risk another assault. He was faced with the prospect of a long siege to starve O'Neill into submission. His return to England would have to be delayed if he were to avoid the dishonour of returning under the cloud of defeat.
Although O'Neill had repulsed the English attack, several hundred of his men had been killed and his ammunition was exhausted. Almost no food remained for the garrison and people of the town. Realising that any help from Ormond was unlikely to arrive in time, O'Neill decided to evacuate his troops. The night after the assault, the Irish garrison slipped away under cover of darkness, crossing the River Suir to the south of the town where no English troops were posted. Next day, John White, the Mayor of Clonmel, sent a message to Cromwell asking for terms. Anxious to bring the costly siege to an end and not realising that O'Neill and his soldiers had gone, Cromwell granted generous terms, guaranteeing the lives and property of the townspeople. Although he was furious when he learned that White had outwitted him, Cromwell nevertheless kept to the terms.
Cromwell sent cavalry in pursuit of O'Neill's column, which was making for Waterford. Although a number of stragglers were cut down, the main body escaped. On arriving at Waterford, however, O'Neill and his troops were refused entry into the town by the governor, Thomas Preston, the former Confederate general and rival of Owen Roe O'Neill, who claimed that he did not have food to spare for the Ulstermen. O'Neill was obliged to disperse his troops into small groups and order them to make their way back to Ulster as best they could.
S.R. Gardiner, History of the Commonwealth and Protectorate vol. i, (London 1903)
Peter Gaunt, The Cromwellian Gazetteer, (Stroud 1987)
James Scott Wheeler, Cromwell in Ireland, (New York 1999)