Mac Suibhne: MacSweeney ("Donegal, History & Society", Geographic Publications, 1995.)
Author: Fergus Gillespie, Chief Herald of Ireland.
The Mac Suibhne family are of Scottish origin and did not settle permanently in Tir Conaill until the beginning of the fourteenth century, when they became gallóglaigh, or hired mercenaries, to the Ó Domhnaill kings. They did, however, claim a remote Irish ancestery, tracing their descent from Ánrothán, son of Áed, son of Flaithbertach Ó Néill, king of Cenél Eóghan, who died in 1036.
According to Leabhair Chlainne Suibhne, after Áed's death his son Ánrothán was chosen as king despite his brother, Domnall, who was the rightful heir. Domnall then cursed Ánrothan who gave up the kingship and departed for Scotland with his followers. There he married the daughter of the king of Scotland. His great-grandson was Suibne from whom the Clann tSuibhne descend. The story of the descent of Clann tSuibhne from the Ó Néill kings of Cenél Eóghan may have been a convenient fabrication in order to give the family a Millesian pedigree and thus an accepted place in medieval Tír Conaill. W. D. H. Sellar, however, has argued most convincingly that the story is not unlikely and that Clann tSuibhne and other Scottish familes such as Lamont may well be descended from the Ó Néill family.
As gallóglaigh the Mac Suibhne family were certainly unusual, for they soon became lords of vast territories in Tír Conaill and developed a special relationship with its Ó Domhnaill kings. In this they differed greatly from other gallóglaigh families in medieval Ireland, such as those of Mac Cába and Mac Somhairle, who were totally dependent on whoever wished to hire their services. The earliest reference to the Mac Suibhne in Ireland is in 1267 when Murchadh Mac Suibne was taken prisoner by Domnall Ó Conchobair and delivered to the Earl of Ulster, in whose prison he died. This Murchad was a son of Máel Muire an Sparáin, a Scottish lord whose seat was the modern Castle Sween in Kintyre, and whose father was Suibne, the eponymous ancestor of the Clann. Suibne's floruit was 1200 and we know that Máel Muire was still alive in 1262. (Murchad's mother, Ben Mide, daughter of Toirdelbach Ó Conchobair, king of Connacht, died in 1269.)