Fermanagh is in North Ireland while all the other neighbouring counties are within the republic. The River Shannon and Lough Allen divide Leitrim into North Leitrim and South Leitrim. At least three of the O’Rourkes were kings of Connacht, one of them having built the tower known as O’Rourkes Tower at Clonmacnoise. In ancient times Leitrim formed the western half of the kingdom of Breifne. This region was long influenced by the O'Rourke family of Dromahair, whose heraldic lion occupies the official county crest to this day. BREIFNE is the name given to the ancient territory which covered the counties of Cavan, Leitrim, part of Meath and part of Sligo.


The ancient kingdom of Connaught comprised the present counties of Galway, Mayo, Sligo, Roscommon, and Leitrim, together with Clare, now in Munster, and Cavan, now a part of Ulster; and was divided into Tuaisceart Conacht or North Connaught, Deisceart Conacht or South Connaught, and Iar Conacht or West Connaught. North Connaught was also called Iachtar Conacht or Lower Connaught; as was South Connaught called Uachtar Conacht or Upper Connaught. From Brion, are descended a group of families known as Uí Briuin. One of these families pushed north between 700 and 800 A.D. and had taken over much of the area now called Leitrim. They were referred to afterwards as the Uí Briuin Bhreifne. It was not until the eleventh century that family surnames came into general use in Ireland. The Irish Annals record a son of Sellachan (aka Ceallach) by the name of Tighearnán, who is noted as a King of Bréifne in the Irish annals, his obituary dated about the year 888. This Tighearnán had been noted with 12 sons, one of whom was named Ruarc, the ancestor of the Ó Ruaircs (O'Rourke, et al). Ruarc and some of his brothers were noted in the Annals as lords of Bréifne, with Ruarc's obituary appearing between the years 892-898. Ruarc and his son Art were apparently men of importance in the province of Connacht (aka Connaught). Art's son Ferghal (aka Sean Ferghal) was the first of the Ua Ruaircs to become King of Connacht, a milestone event occurring about the middle of the 10th century. As a grandson of Ruarc, Ferghal was among the first Bréifne kings entitled to be called Ó Ruairc. Ferghal must have been a powerful warrior since the kingship of Connacht had previously been dominated by the Uí Fiachrach and by other branches of the Uí Briúin. The next King of Breifne had connections with the above Murchadh Ó Maeleachlain of Meath, responsible for the death of Giolla Srònmhaol Ó Ruairc. His name was Tigernan O Ruairc and he was supported by Murchadh as the next King of Breifne about the year 1124. Tigernan was described as a 'young cousin of the Gilla Strònmael,' and he married Murchadh O Maeleachlain's daughter Dearbhforgaill (Dervorgil). The older Irish genealogies place Tigernan as a descendant of Domnall who was one of two known sons of Ualgharg, the royal heir of Connaught who died in 1085. In the the years 1169 and 1170, more forces from Wales and England arrived in Ireland to support Diarmaid Mac Murchadha and his greater ambitions.

County Leitrim (Irish: Contae Liatroma) is one of the counties of the island of Ireland province of Connacht, in the west of the island. The County of Leitrim was created under the reign of the British Queen, Elizabeth I. In the sixth and seventh centuries, Leitrim was inhabited by various population groups. The groups included the Dartraige, Calraige and the Conmaicne Rein. Niall of the Nine Hostages had a brother named Brion who formed a kingdom west of the Shannon River around Co. Roscommon. Leitrim in Gaelic is "Liath Dhroim" or gray ridge.

A section of Connacht and Ulster was known as the Kingdom of Bréifne which covers both Co Leitrim and Co Cavan. West Bréifne covers all of Co Leitrim and the two baronies in Co Cavan, Tullyhunco and Tullyhaw. West Bréifne was known as Shieve an Ierin Westwards. The dividing line separating West and East Bréifne is the river Graine, now the Woodford River at Ballyconnell. Lorcan O'Runai in his book "From Rosclogher to Rooskey" list the more well known families of North Leitrim. The rulers of Muintir Kenny were of the family of Mac Con Snamha of Lough Allen. The MacTernans, a Sept of the O'Rourkes, descended from Tighearnan O'Rourke who ruled the land called Teallach Donnchadha anglicized to Tullyhunco a barony in the present Co Cavan, Ulster.

Around 750 A.D., the oldest brother of Niall of the Nine Hostages was Bryan, the first king of Connacht. Bryan's son was Duachas Golach, the first Christian king. His son was Owen Sreibh, his son was Muredach, his son was Fergus and his son was Eochy Tiorm Charna. Eochy Tiorm Charna had two brothers, Fergus and Duach Teary-Unk. Fergus was the ancestor of O'Rourke, (West Breffine), lord over O'Reilly, MacTernan or Kiernan and MacGauran, down the line to Tiernan, Prince of West Breffine. West Breffine consist of County Leitrim and two baronies in Co Cavan, Tullyhunco and Tullyhaw. Brefine means hilly country in Gaelic. At this time in history the term O'Rourke may mean a set of people living in a certain area rather than just one single family.

Dromahaire (Droim a dhá Eathair, Droim dhá Thiar (alt.) in Irish) is a village in County Leitrim. Of the two Irish possible names, Droim a dhá Eathair ("Ridge of the two air-demons") is the oldest. This is a small picturesque village which is 12 miles from Sligo town. Built on the banks of the Bonet River which flows into Lough Gill, it is a town rich in history. Seate of the O'Rourkes, the ancient High Kings of Breifne, one of the old Celtic kingdoms. It is also the place from which Devorgilla fled with her lover, Diarmuid McMurrough, an act which set in train a series of internal divisions in ancient Ireland, leading ultimately to the invasion of Ireland by the English. The village was modelled on a village in Somerset by Lord Leitrim. The Barony of Drumahaire, Co Leitrim, Connacht is one of 331 Baronies in Ireland. Drumagheire as it was called in the old days is 117,087 acres that runs along the north bank of Lough Allen and spans the middle of Co Leitrim bordered on the west by Co Sligo and on the east by Co's Fermanagh and Cavan Drumagheire is in the Poor Law Union of Manorhamilton with a very small section in the Poor Law Union of Carrick-on-the-Shannon. It is in the Probate District of Ballina and the Civil Dioceses of both Kilmore and Ardagh. It covers the civil parishes of Cloonclare, Cloonlogher, Drumlease, Drumreilly, Inishmagrath, Killanummery and Killarga. Drumahaire includes the Catholic parishes of Cloonclare, Drumlease, Killargue, Drumreilly, Inishmagrath, Killenummery and Killerry. Drumlease means the ridge of huts. It is in its own valley surrounded by the hills of North Leitrim. It sits on the bank of the River Bonnet and was laid out by the chief land-lord of the day, Lord Lane-Fox based on a Somerset village in England. Roscommon and through inheritance it passed to a wealthy and long established Yorkshire family named Fox. The Fox family adopted the name Lane, becoming Lane-Fox. The Lane-Fox family were the main landlords in the town and the surrounding land for the next 150 years.

A sept in Co. Leitrim closely related to the O'Rourkes, Lords of Breffny, also assumed the suname MacLochlainn from an ancestor named Lochlan. This sept appears in the State Papers of 1591 as one of the chief fighting forces of the O'Rourke chieftains who "shared the lands of Ylaugh and Cleanlough in Co. Leitrim as their inheritance" with the MacMorrices and the MacTiernans of Clann Tiernan. That they were an important local sept is evidenced by the same document of 1591 which states "they had never bonnaught of O'Rourke but only their shares in the preys and spoils that were taken."

The O’Rourkes were in control of most of Leitrim rendering them the most powerful family in Leitrim until the flight of the Wild Geese in 1691. The present day Leitrim crest has the O’Rourke lion on it. Close ties initially existed with East Breifne, now County Cavan, and the O'Reilly clan seated there. Four of the name appear in the 1609 pardon lists of King James I along with the O'Rourke chieftains. Two of the name received grants of land at about the same date in the Barony of Drumaheir in Leitrim County. The sept appears to have been fairly numerous: in the Census of 1659 the combined returns for the Baronies of Drumheir and Roscloger record the names of 32 MacLoughlin families. The Anglo-Normans invaded in the thirteenth century and occupied the south of Breifne until the exile of Irish landholders in 1620.

Killeshandra and Croghan comes from the Irish meaning the 'Church of the Old Fort'. This church was sited on an old semi-circular 'rath' or fort overlooking the lake that is now-a-days known as the Town Lake. Records in the Papal Annates concerning the appointments of clergy to the church date from 1411 and in 1436 were are told that the patron saint of the church was St. Brigid. In the 11th century two MacTighernan families were noted in Irish history as chiefs, Lord McTernan of Tullyhunco, Co Cavan and the McTernans of Co Fermanagh. During the later middle ages the dominant family or clan in the area was the McKiernan family. The land of Tullyhunco, which was the McKiernan territory, was included in the rectory of the same name and its church was at Killeshandra. The chieftains of the McKiernans had their dwelling place at Croghan and the family had managed to maintain a certain degree of autonomy thanks to their geographical position between the two hostile septs of the O'Reilly and the O'Rourke.

A sept in Co. Leitrim closely related to the O'Rourkes, Lords of Breffny, also assumed the suname MacLochlainn from an ancestor named Lochlan. This sept appears in the State Papers of 1591 as one of the chief fighting forces of the O'Rourke chieftains who "shared the lands of Ylaugh and Cleanlough in Co. Leitrim as their inheritance" with the MacMorrices and the MacTiernans of Clann Tiernan, also MacCahal Reagh, MacMurray, MacTiernan, McNeil. That they were an important local sept is evidenced by the same document of 1591 which states "they had never bonnaught of O'Rourke but only their shares in the preys and spoils that were taken." Four of the names appear in the 1609 pardon lists of King James I along with the O'Rourke chieftains. Two of the name received grants of land at about the same date in the Barony of Drumaheir in Leitrim County. The sept appears to have been fairly numerous: in the Census of 1659 the combined returns for the Baronies of Drumheir and Roscloger record the names of 32 MacLoughlin families.

The Abbey of Creevelea, across from the town of Drumahaire on the bank of the Bonnett River in Co Leitrim is the family chapel of the O'Rourkes the kings of Drumahaire.

The 10th and the 11th century kingship of Connacht was held by three O'Rourkes. The name O'Rourke comes from the Norse name, Hrothrekr. Lords of Breifne until Cromwell appeared on the Irish stage in the mid 1600s. In the O'Rourke pedigrees there are 19 chiefs, all called Tiernan. Manorhamilton, the largest town in North Leitirm was originally known as O'Rourke's Little Field. The Plantation castle that replaced the O'Rourke Castle very near the O'Rourke family chapel, Abbey of Creevelea on the Bonnett River, now officially known as Parke's Castle and was built by the stronghold of the exceedingly powerful O'Rourke clan of Breffni from the 13th century until the end of the 16th century.

The McTernans of Tullyhunco, Co Cavan prevented the inauguration of Domhnall O'Ruairc by the king of Ulster, Uí Neill at the historical inauguration site of Corann Cruachan which is very near the McTernan historical home of Teallach Dhonnchadh or (Tullyhunco). The Barony of Tullyhunco comprises three civil parishes: Kildallan in the NW, Killashandra in the center and Scabby in the SE. All the parishes border Co Leitrim. The root Gallic word of Tully means small hill.