The siege of the town began on 18 April. James and de Rosen returned to Dublin and left Lieutenant-General Jacques de Fontanges, comte de Maumont, in command. However, Maumont was killed during a sally on 21 April and the command devolved to Hamilton, who lacked experience in sieges. De Rosen came back from Dublin to Derry in June. The siege was finally abandoned after 105 days on 31 July 1689. Richard Hamilton retreated with the army southwards.