In August 1649, Commonwealth forces under Oliver Cromwell landed near Dublin to reclaim control from an alliance between Royalists and Irish Confederates.

After arriving in Ireland, Cromwell's forces struck hard and fast north of Dublin capturing Drogheda, Belfast, and Carrickfergus.

[3][4] On 29 January 1650, taking advantage of a mild winter, Cromwell reinitiated his campaign in southern Ireland with the overall objective of capturing both the Confederate capital of Kilkenny and the fortified stronghold Clonmel.

Cromwell began first by dividing his army into multiple columns to attack and capture the outlying Royalist garrisons in the provinces of Munster and Leinster.

An Irish officer serving as a part of the defence force for Kilkenny, Captain Tickle, had been bribed to betray the city by opening one of the gates to the Parliamentarians.

When Cromwell's forces arrived at the appointed time and place to enter the city, however, the Parliamentarians found the intended entry point securely closed and defended.

[2][1][5] Shortly thereafter, as Cromwell prepared to besiege the city, the leader of the Royalist alliance, the Duke of Ormond and the Confederate Commissioners fled Kilkenny to the safety of King John's Castle 90 kilometers to the west in Limerick.

[1][5] Adding to Butler's difficulties, the normal complement of able bodied soldiers in the garrison had been reduced from a force of 1,000 infantry and 200 horse to approximately 300 men over the winter of 1649-1650 by the plague.

Butler rejected Cromwell's offer the next day causing the Parliamentarians to invest the city and begin the siege and attack in earnest.

Then to make matters even worse at that time, Parliamentarian General Ireton arrived with a column of 1,500 men to reinforce Cromwell's forces if needed.

[9] Seeing no way to successfully defend Kilkenny's High Town and castle against such an onslaught, Butler accepted Cromwell's terms of surrender admitting to himself there was nothing he could do.

The Royalist and Irish Confederate officers and soldiers were given safe conduct to march away from the city with their colours flying, taking along with them their bags, baggage, horses, and arms.