Osraige (Old Irish) or Osraighe (Classical Irish), Osraí (Modern Irish), anglicized as Ossory, was a medieval Irish kingdom comprising what is now County Kilkenny and western County Laois, corresponding to the Diocese of Ossory. The home of the Osraige people, it existed from around the first century until the Norman invasion of Ireland in the 12th century. It was ruled by the Dál Birn dynasty, whose medieval descendants assumed the surname Mac Giolla Phádraig.