Kings of Osraige

The kings of Osraige (alternately spelled Osraighe and Anglicised as Ossory) reigned over the medieval Irish kingdom of Osraige from the first or second century AD until the late twelfth century. Osraige was a semi-provincial kingdom in south-east Ireland which disappeared following the Norman Invasion of Ireland. Except for a period in the sixth century, the kingdom was ruled continuously by a single dynasty which is known to history by several names: Dál Birn being the first general term for the native ruling lineage of Osraige, and later adopting the surname Mac Giolla Phádraig by the end of the tenth century. This same dynasty eventually outlived the collapse of the kingdom into a lordship, and remarkably continued into the first half of the 20th century as landed gentry of varying rank. Thus, the kings of Osraige form one of the oldest continuous dynasties in Western Europe. By 1541, the Mac Giolla Phádraig clan had adopted the surname Fitzpatrick, which is still in use today.

Osraige was largely a buffer state between the provincial kingdoms of Leinster and Munster. It was bounded to the south by the rivers Suir and Barrow, though it originally extended to the sea and its rulers had some influence over the Norse kings of Waterford. In the north, it may have once stretched over the Slieve Bloom mountains and reached the River Shannon, but in the historic era it generally stayed to the south of these mountains, the boundary generally being the river Barrow.

In a clockwise direction (starting at 12:00) it was bordered by the kingdoms or lordships of Éile, Ui Duach, Loigis, Ui Drona, Uí Cheinnselaig, Desi Mumhain, and Eóganachta Caisel. Its main town and dynastic capital was Kilkenny. The name Osraige is said to be from the Usdaie, a tribe that Ptolemy's map of Ireland places in roughly the same area that Ossory would later occupy. Other tribes in the vicinity were the Brigantes and the Cauci. The Osraighe themselves claimed to be descended from the Érainn people. Modern day County Kilkenny and part of west County Laois comprise the core area of what was this kingdom.

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