[b] However, their defection caused a split with Ulster Catholic Eoghan Ó Néill, whose troops were some of the most effective in the Confederate army, and who now made a separate truce with Michael Jones, Commonwealth governor of Dublin.

[3] Seeking to secure Ireland as a base for the new king, Charles II, Ormond besieged Dublin in June, but was weakened by having to divert resources against Ó Néill.

On 2 August, Jones defeated him at Rathmines, a victory that allowed 12,000 mostly veteran New Model Army troops under Oliver Cromwell to land near Dublin unimpeded.

At a Council of War held at Drogheda on 27 August, Ormond and his commanders agreed to avoid open battle, but instead strongly hold key ports along the east coast.

This port was an important base for Confederate privateer attacks on English merchant ships, and provided a link with the exiled Royalist court in France.

Cromwell's force of around 6,000 arrived outside the town on 2 October; two days later, a detachment led by Jones surprised the Royalist garrison of nearby Rosslare, giving Deane a secure harbour.

[13] In his report to London, Cromwell suggested this was retribution for the killing of Protestants earlier in the rebellion, although he regretted the damage prevented him from using Wexford for winter quarters.

[14] His personal responsibility is still a matter of debate; historians including Tom Reilly, Nicholas Canny, and Roger Hainsworth, suggest the assault was launched without his approval, and he was unable to control his troops once the plundering began.

[16] Although the killings at Drogheda and Wexford were on a larger scale, Irish Catholics captured in England and Scotland, or taken at sea, were routinely executed throughout the war, including Philiphaugh in 1645, and Dunaverty in 1647.

[17] The loss of Wexford ended any chance of Charles II landing in Ireland; the Royalist fleet, commanded by Prince Rupert, now broke out of Kinsale and headed for Lisbon.