of their most effective fighting force in the north. Despite this, by late July, Ormond's combined Royalist/Confederate army controlled most of Ireland. Ormond's defeat at Rathmines on 2 August allowed Cromwell and an army of 12,000 to land in Dublin unopposed. After capturing Drogheda on 11 September, his main force headed south towards Wexford; Colonel Robert Venables was sent north with three regiments, or around 2,500 men, to take control of Ulster. Munro's garrisons surrendered with minimal resistance, and by the end of September, Venables had occupied Dundalk, Carlingford, Newry, and Belfast. These were accompanied by the mass expulsion of Scots settlers, as punishment for their defection; when Coote captured Coleraine on 15 September, he massacred the largely Scottish garrison. Ó Néill's death in November 1649 and Coote's defeat of a combined Royalist/Covenanter force at Lisnagarvey in December left the Catholic Ulster army as the only remaining opposition to the Commonwealth in the north. At a meeting at Belturbet on 18 March 1650, Heber MacMahon, Catholic Bishop of Clogher, was appointed in his place. Although a leading figure in the Confederation, MacMahon had no military experience and opposed the alliance with Ormond's Royalists; his election was essentially a compromise between supporters of Henry, Ó Néill's son, and his cousin, Felim Ó Néill. Campaign By 20 May, MacMahon and his deputy Richard O'Farrell had assembled an army near Loughgall, with 5,000 infantry and 1,000 cavalry. They lacked both arms and artillery but after Ormond promised to send these from Connacht, they marched north, intending to divide Coote's troops at Derry from those commanded by Venables at Carrickfergus in the east. To do this, MacMahon established a line of garrisons with its northern end at Ballycastle, then moved south, intending to cross the River Foyle just below Lifford and maintain contact with Ormond through Ballyshannon. At this point, Coote had only 1,400 men and seemed vulnerable; the Irish crossed the river on 2 June, beating off an attack by the Commonwealth cavalry and occupied Lifford, where they spent the next two weeks and Coote withdrew to Derry. However, the supplies promised by Ormond failed to arrive, leaving MacMahon short of provisions, while on 18 June Coote was joined by an additional 1,000 infantry under Colonel Roger Fenwick sent from Belfast. At the same time, detaching men for the new garrisons left MacMahon with around 4,000 infantry and 400 cavalry. MacMahon now relocated