The Mac Suibhne family did not permanently settle in Ireland before the beginning of the 14th century, when they became Gallowglass soldiers for the Ua Domnaill dynasty of Tír Chonaill.
Leabhar Clainne Suibhne states that after Áed's death, although his older brother Domnall was the rightful heir, Ánrothán was chosen instead to be king.
[5] Also in the same year Alexander III of Scotland granted Lochranza Castle to Walter Stewart, Earl of Menteith.
With the arrival of the royal fleet Norse control in the Western Isles and Argyll was re-established, and the Norwegian king's force was strengthened by Islesmen.
[8] Between 1301 and 1310, John MacSween was in the service of the English in the hope of keeping alive his family's claim against the Menteiths.
The Balliols, Comyns and MacDougalls taking the side of the English in opposition to the Macdonalds and the Bruce, crowned Robert I of Scotland on 25 March 1306.
[8] A contingent of the MacSweens eventually re-established themselves at Donegal as Gallowglass mercenary soldiers and became the progenitors of Clan Sweeney.
Some of those who stayed on in Scotland formed into the Clan MacQueen, a branch of whom later joined the powerful Chattan Confederation.
According to Niall Campbell, 10th Duke of Argyll, other MacSweens who remained in Scotland became known as the MacEwens of Otter, whose chiefly line may have become extinct in the 17th century.
[1] Once established in Ireland the Clan Sween controlled large territories, and was divided into three branches: Rathmullan was the seat of MacSuibhne Fanad for the next 400 years, during which time their influence extended from Donegal into Connacht and Munster.
In Ireland they were inaugurated in Kilmacrennan, County Donegal, where MacSuibhne Fanad became influential allies of the O'Donnell of Tyrconnell.
[15] Logan also noted that the war-cry of the Mac Sweins was "Battalia-abu" (The noble staff, victorious), from the battle-axe they bore in their Arms.
The male line of the ruling Mac Suibhnes soon failed after Eoin, when both his son, Suibne, and his brother, Toirdelbach, died without heirs.
The invaders were opposed by the ruling Ó Domhnaill who was aided in part by Maol Mhuire Mac Suibhne, son of Toirdhealbhach Ruadh.
Neachtain's son, Toirdhealbhach Cairbreach Ó Domhnaill, assumed the vacant kingship of Tír Conaill.
[17] In 1460 Aodh Ruadh Ó Domhnaill and Maol Mhuire Mac Suibhne were released from captivity, and in the following year they both defeated Toirdhealbhach Cairbreach near Mulroy Bay.
Maol Mhuire Mac Suibhne ruled for eleven years before being killed on Easter Tuesday, 1472 while fighting alongside Aodh Ruadh against Énrí Ó Néill.
By 1619 he is recorded as having 2,000 acres (8.1 km2) allotted to him, called Roindoberg and Caroocomony, on which he "built a good bawne, and a house, all of lime and stone, in which with his family, he dwelleth.
"[17] Domhnall's son, Dormhnall Gorm, married a daughter of Eoghan Óg Mac Suibhne na dTuath and had ten children, before dying in 1637.
[17] Dormhnall Gorm's sons, Domhnall Óg and Aodh Buidhe are recorded having lands in Clondavaddog in north Fanad, held forfeit after the Irish Rebellion of 1641.
[18] In 1543 MacSuibhne na d'Tuath and his brother, Brian, were held as prisoners at Inis Mhic an Doirn (Ruthland Island, parish of Templecrone).
By 1545 MacSuibhne na d'Tuath had died the lordship was taken over by his son, Eoghan Óg, who was killed fighting in 1554 at Ceann Salach (in Cloghaneely).
Murchadh Mall and Mac Suibhne Fánad (Toirdealbhach Óg) were killed in 1570 by Clann Domhnaill Gallóglaigh, at Dun na Long near Strabane.
In 1592 Eoghan Óg attended the inauguration of Aodh Ruadh Ó Domhnaill as lord of Tír Conaill.
Maol Mhuire was then held prisoner on a ship on the River Foyle, near Derry, but managed to escape with the aid of a prostitute.
The eldest of the grandsons, Toirdhealbhach was also listed as the High Constable of Connacht and was killed with two of his brothers, Donn Sléibhe and Donnchadh in 1397.
[19] Killybegs (Irish Gaelic: Na Cealla Beaga, meaning 'the small churches'), was also controlled by Mac Suibhne Boghaineach.
[19] In 1513 Killybegs was plundered by Eoghan Ó Máille and the crews of three ships, who were, however, unable to return home to Connacht with their prisoners because of stormy weather.
Ruaidhrí Ballach Mac Suibhne then requested to Maghnus Ó Domhnaill to be installed as lord of Banagh, but was refused.
Aodh Ruadh's mother, Iníon Dubh, in response mustered a large force of Scots and also the Mac Suibhne branches of Na Tuatha and Fanad to oppose Domhnall.