Londonderry and Dundalk, 1649
The signing of the Second Ormond Peace in January 1649 secured an alliance against Parliament between the Confederate Irish, Lord Inchiquin's Munster Protestants and the Royalists. Furthermore, the execution of King Charles I and the declaration of the Commonwealth in England alienated the Ulster Scots and brought them into Ormond's coalition. The Parliamentarians were confined to three main enclaves in Ireland: the garrison of Colonel Jones at Dublin and those of Colonel Monck and Sir Charles Coote at Dundalk and Londonderry in Ulster.
In late March, the Lagan army of western Ulster besieged Sir Charles Coote at Londonderry. Coote had seized Londonderry for Parliament in December 1648 and arrested the Lagan commander Sir Robert Stewart, whom he sent as a prisoner to London. The town was strongly fortified and as they possessed no siege artillery, the Laganeers were obliged to blockade the garrison and attempt to starve it into surrender. Siege works were set up to cut off all roads into the town and a fort was built on the banks of the River Foyle to prevent supplies and reinforcements arriving by sea. However, the guns of the fort were ineffective and failed to prevent supply ships getting through. Coote conducted an aggressive defence, regularly sending skirmishers and raiders out from the garrison into County Londonderry. However in May 1649, Sir Robert Stewart escaped from imprisonment and returned to Ulster. The blockade of Londonderry became more effective under Stewart's direction and in early July, Sir George Monro joined the besieging army with an additional 2,000 Ulster Scots and twelve light field guns that were capable of sinking any supply ship that tried to break through the blockade. By mid-July, Coote's garrison was desperately short of supplies.
Meanwhile in south-east Ulster, Colonel Monck's garrison at Dundalk was blockaded by the Scottish army and British settlers. Monck gained help from an unexpected quarter when Owen Roe O'Neill was forced to withdraw into Ulster by the combined forces of Ormond's coalition. In May 1649, O'Neill and Monck signed a three-month truce and agreed to support one another against their common enemy. The presence of O'Neill's army protected Monck's garrison during May and June but further south, Ormond was gathering his forces for an assault on remaining Parliamentarian strongholds. While Ormond blockaded Dublin, Lord Inchiquin marched north to besiege Drogheda, which surrendered in early July. Inchiquin then advanced on Dundalk.
Monck appealed to O'Neill for help and agreed to supply O'Neill's army with twenty barrels of gunpowder in return. O'Neill sent Lieutenant-General Farrell with troops to escort the powder convoy from Dundalk to the Irish camp at Crossmaglen. However, Farrell's men got drunk with their new allies and were attacked by Inchiquin's cavalry on the return journey to Crossmaglen. The Irish were routed and the supply of gunpowder was captured by Inchiquin's troopers. After this disaster, O'Neill withdrew into western Ulster out of Inchiquin's reach. Morale amongst Monck's troops collapsed and most of the Dundalk garrison deserted to Inchiquin. On 24 July, Monck surrendered Dundalk. He was granted a pass to return to England, where he faced a parliamentary enquiry into his unauthorised treaty with O'Neill. Apart from a small, isolated garrison at Enniskillen, Londonderry was the last remaining Parliamentarian stronghold in Ulster.
Early in August 1649, O'Neill's army arrived in the vicinity of Londonderry. Thanks to his truce with the Parliamentarians, O'Neill was the unlikely ally of Sir Charles Coote, who agreed to supply the Ulster Irish with ammunition and gunpowder. The Lagan army and the Ulster Scots besieging Londonderry were not strong enough to challenge O'Neill in battle. The five-month siege was lifted as the Laganeers withdrew towards Connacht and Monro's forces retreated to Coleraine and Belfast. O'Neill's disruption of the coalition armies in Ulster unwittingly prepared the way for the conquest of the province By Parliamentarian forces later in 1649.
S.R. Gardiner, History of the Commonwealth and Protectorate, vol.i (London 1903)
James Scott Wheeler, Cromwell in Ireland, (New York 1999)