Galway was the last city held by Irish Catholic forces in Ireland and its fall signalled the end to most organised resistance to the Parliamentarian conquest of the country.

Galway was garrisoned by Irish Confederate soldiers under Thomas Preston, many of whom had reached the city after an unsuccessful defence of Waterford.

However, Galway remained open to the west and Irish general Richard Farrell was quartered in Connemara with 3,000 more troops.

In November 1651, after the fall of Limerick, Henry Ireton, the Parliamentarian commander in Ireland, decided to make the capture of Galway the main priority for his forces.

In March, a conference of Irish officers in Galway, including Clanricarde, decided to begin negotiations for terms of surrender.