The March on Dublin, 1646
Following the failure of the Marquis of Ormond's peace initiative in September 1646, a new Confederate Supreme Council was appointed by the Irish clergy, with the hardline Archbishop Rinuccini as its president.
The new council lost no time in planning an immediate attack on Dublin using both the Ulster and Leinster armies. The combined army of around 18,000 men was the largest ever fielded by the Confederates. It was commanded jointly by the rival generals O'Neill and Preston. Towards the end of September 1646, the two armies advanced separately towards Dublin, seizing British outposts on their lines of march and joining forces at Kilkea in County Kildare around 8 October. Meanwhile, the Marquis of Ormond ordered the destruction of all crops, mills and bridges within an eight-mile radius of Dublin to hamper the Irish advance.
Rather than demand the surrender of Dublin, Archbishop Rinuccini opened negotiations with Ormond which became protracted when the Marquis of Clanricarde began separate negotiations with General Preston in an attempt to bring the Leinster army over to the Royalists. By early November, the combined Confederate army was encamped around Leixlip and Lucan, eight miles west of Dublin, but it was desperately short of supplies. With the onset of winter weather, the siege of Dublin broke up by order of the Supreme Council in mid-November 1646.
The campaign against Dublin was completely ineffective and lost the Confederates their only chance of taking the city. Alarmed at the prospect of a Catholic army at Dublin's gates, the Marquis of Ormond opened negotiations with the English Parliament. Unable to conclude a binding peace with the Confederates and discouraged by the defeat of the Royalists in England, Ormond offered to resign as lord-lieutenant of Ireland and surrender Dublin to Parliament rather than allow the city to fall into Catholic hands.
Commissioners from the English Parliament arrived at Dublin in November 1646 to begin negotiations. In June 1647, Colonel Michael Jones arrived with 2,000 New Model Army troops to garrison the city. Ormond formally surrendered his sword of office to Parliament on 28 July 1647.
Pádraig Lenihan, Confederate Catholics at War 1641-49, (Cork 2001)
C.P. Meehan, The Confederation of Kilkenny (Dublin 1846)
Jane Ohlmeyer, The Civil Wars in Ireland (in The Civil Wars, a military history of England, Scotland and Ireland 1638-60), Oxford 1998
C.V. Wedgwood, The King's War (London 1955)