The Ó h-Anluain (anglicised as O'Hanlon) family was an agnatic extended family comprising one of a string of dynasts along the Ulster-Leinster border. Depending on the advantage to the clan, the Chief of the Name—The O'Hanlon—supported either the Earl of Tyrone or authorities within the English Pale. During the 15th century, ties were close with the famed Earls of Kildare. Frequently, members of the clan would fight on both sides during a rebellion. Some would be outlawed; others pardoned; some ending up on the winning side.
The heart of "O'Hanlon's Countrie" was centered on south central Ulster, much of it being in what is now the Republic of Ireland. The first O'Hanlon on record is Flaithbheartach Ua h-Anluain, lord of Ui Niallain, whose murder in the year 983 AD is recorded in the Annals of the Four Masters.
The anglicised version of the name is usually given as Hanlon or O'Hanlon, but there are many variants: Handlon, Handlan, Hanlan, Hanlen, Hanlin, Hanlyn etc. Occasionally some variants of the names Hanly, Hanley and Handly are also derived from Ó h-Anluain, although Hanly is usually the anglicised form of Ó h-Ainle, an ancient Roscommon sept (the oldest on record is Donal O'Hanly, Bishop of Dublin from 1085 to 1096).
O'Hanlon's Country
The ancestors of the Ó h-Anluain sept originated in the kingdom of Airgialla. By the 5th century A.D. the sept held territory in and around the modern barony of Oneilland, County Armagh, Northern Ireland, on the southwest shore of Lough Neagh. As the O'Neills rose in prominence from Dungannon to the west, the O'Hanlons moved to territory west of Armagh City. For half a millennium, they served as kings of Orior. The chieftain's name was synonymous with the territory which was better known as "O'Hanlon's Country". It comprised about one-third of modern County Armagh, predominantly the eastern third, and also included a large tract of County Louth, from Faughart to Ravensdale, and then over the Cooley mountains to Omeath near Carlingford. The peak of land acquisition was in 1504; in 1505 the territory beyond the Gap of the North was granted to the Earl of Kildare. Two of the earliest maps of Ulster, Jobson's Ulster maps (c. 1590) and Norden's map of Ireland (1610), both show O'Hanlon's Country. In 1586, when Sir John Perrot created the County of Armagh, O'Hanlon's country accounted for one of the five baronies: Armaghe, Toaghriny, Orier, Fuighes (Fews) and Onylane (O'Neilland). In later times "Orier" became the Baronies of Orior Upper and Orior Lower, the southernmost two of Armagh's eight Baronies. It is often overlooked that the Gaelic territory of Orior predates and extended beyond the Barony of that name in County Armagh. O'Hanlon's Country extended southwards into northern County Louth and to the East it encroached slightly into County Down. Before the county lines were finalised, some old maps show the old O'Hanlon seat of Loughgilly in County Down.
O'Hanlon strongholds
Anciently, the O'Hanlons – when sitting as kings of Aithir – kept their residence, and the sept's assembly, at Loughgall (Loch gCál), north of Armagh city. Even after the sept moved east toward Loughgilly, Loughgall was retained as a summer residence. When Edmond Mortimer arrived in Ireland in 1380 as Lord Justice, the chief O'Hanlon was recorded as amongst the righdamhna (those eligible to become a tanist, or heir-apparent, of an Irish kingdom) that were required to pay their court to him. The rock of Tanderagee rose to support the family's castle. Having secured the northern lowlands of County Armagh and the highlands approaching and surrounding the Ring of Gullion, the O'Hanlons located the chieftain's gateway strongholds on the approaches from Armagh and eastern Ulster in the north, and Dublin and the English Pale in the south." The northern roads converged on the modern-day village of Tandragee; the approaches from Dublin and the English Pale had to force the Gap of the North, and the chieftain's stronghold adjacent to Forkill at Mullagh. The third stronghold, Mullaghglass, guarded the road north from the English frontier town of Newry. Closer to the center of the O'Hanlon lands than Tanderagee and Forkill, Mullaghglass is also the easternmost edge of a tract of land stretching from the Newry vale to the Fews, passing Camlough lake and the northern slope of Sliab Gullion, to which the sept retreated after the fall of the Gaelic order.