Battle of Knocknaclashy Boyle had inspired a mutiny among the English Royalist garrison in Cork, causing them to defect to the Parliamentarians. This had outflanked the defences of Irish Confederates and English Royalists, causing them to retreat behind the river Shannon into Connacht, where they held the fortified cities of Limerick and Galway. Henry Ireton went on to besiege Limerick. The only organised Irish forces remaining in south Munster were those of Donagh MacCarthy, Viscount Muskerry, who held out in the mountainous area of west Cork and county Kerry – which was his clan’s native territory. In July 1651, Muskerry set out from
Burning of Cork 1920, the IRA's 3rd Cork Brigade ambushed an Auxiliary patrol at Kilmichael, killing 17 Auxiliaries. This was the biggest loss of life for the British in County Cork. On 10 December, British forces declared martial law in counties Cork (including the city), Kerry, Limerick, and Tipperary. It also imposed a military curfew on Cork city, which began at 10 each night. IRA volunteer Seán Healy later recalled that "at least 1,000 troops would pour out of Victoria Barracks at this hour and take over complete control of the city". IRA intelligence established that an Auxiliary patrol usually left Victoria Barracks