Mac Giolla Phádraig is a native Irish dynastic surname which translates into English as "Son of the Devotee of (St.) Patrick". In the medieval period, the Mac Giolla Phádraigs were hereditary kings of Osraige; today, the anglicised version of the name is commonly "Fitzpatrick".

Upper Ossory was an administrative barony in the south and west of Queen's County in Ireland. In late Gaelic Ireland it was the túath of the Mac Giolla Phádraig (Fitzpatrick) family and a surviving remnant of the once larger kingdom of Ossory. The northernmost part of the Diocese of Ossory and medieval County Kilkenny, it was transferred to the newly created Queen's County, now known as County Laois, in 1600. In the 1840s its three component cantreds, Clarmallagh, Clandonagh, and Upperwoods, were promoted to barony status, thereby superseding Upper Ossory.