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
Brosna, County Kerry of Trughanacmy. Crochaun Mountain is above sea level. Brosna lies close to the Cork/Kerry and Kerry/Limerick borders, and neighbouring towns include Castleisland and Knocknagoshel in Kerry, Abbeyfeale and Mountcollins in Limerick, and Ballydesmond and Rockchapel in Cork. In Samuel Lewis's 1837 "Topographical Dictionary of Ireland", Brosna was recorded as having 2168 inhabitants in 18,013 statute acres. The same entry notes that a "large portion of the land consisted of coarse mountain pasture and bog, the greater part of which might be reclaimed". As of the first half of the 19th century, there were 2 private schools in the area, in