 Sir Henry Sidney shired the county of Sligo, intended to replace the old Gaelic territory system.In AD 542 the Battle of Sligo, in which Eogan Bél, king of Connacht, fell by Fergus and Domnall two sons of Muircheartach son of Erc, and by Ainmire son of Setna and by Naindid son of Dua who were the victors.Whence it was said