MAC LOCHLAINN
MAC LOCHLAINN
A leading family of the Cenél nEógain branch of
the northern Uí Néill dynasty, the Meic Lochlainn
(Mac Loughlin) were descended from Lochlann mac
Máelsechnaill, king of Inishowen, who died in 1023.
There is some confusion among the medieval geneal-
ogists in regard to the ancestry of the Mic Lochlainn,
due to a deliberately forged pedigree drawn up during
the reign of the high king, Domnall Mac Lochlainn
(d. 1121). In reality, the Meic Lochlann were descended
from Domnall Dabaill, son of the Cenél nEógain
king, Áed Findliath, whose other son was Niall
Glúndub, ancestor of the Ua Néill dynasty of southern
Tír nEógain. The Meic Lochlainn, who were known
as the Clann Domhnaill, were a great warrior family,
who suppressed their rivals, the Ua Néills, and then
usurped their genealogy. However, they were greatly
disadvantaged in wider Irish politics by their distance
from the beneficial influence of the Norse towns in
southern Ireland.
Domnall Mac Lochlann, (d. 1121), king of Aileach
and high king of Ireland for twenty years, foiled the
attempts by the Munster high king, Muirchertach Ua
Briain, to subdue the Cenél nEógain. By using the
good offices of the abbot of Armagh, Domnall contin-
ually made peace with Ua Briain from 1099 to 1113.
In 1110, Domnall raided Connacht and seized three
thousand prisoners and many thousands of cattle.
Domnall died in 1121, aged seventy-three, being called
“the most distinguished of the Irish for personal form,
family, sense, prowess, prosperity and happiness, for
bestowing of jewels and food upon the mighty and the
needy.” His son Niall Mac Lochlainn succeeded him
as king of Tír nEógain.
Domhnall’s grandson, Muirchertach Mac
Lochlainn, was high king of Ireland from 1156 to
- A powerful king, Muirchertach counted men
such as Diarmait Mac Murchada, king of Leinster,
among his vassals, and made a policy of dividing rival
kingdoms such as Mide, out among subservient claim-
ants. In 1150, Muirchertach granted twenty cattle and
a five-ounce gold ring to the abbot of Derry. In 1154,
he hired a Norse fleet from the Hebrides and the
Isle of Man to oppose the fleet of Tairrdelbach Ua
Conchobair, king of Connacht. Muirchertach’s flotilla,
however, was defeated in a naval battle off Inishowen.
In the same year, Mac Lochlainn obtained the sub-
mission of the Norse of Dublin and granted them
tuarastal(a ceremonial gift to seal a vassal’s submis-
sion) of 1,200 cattle. In 1157, Muirchertach attended
the synod of Mellifont granting “seven score cows,
and three score ounces of gold, to God and to the
clergy” as well as an entire town-land near Drogheda.
In 1159, Muirchertach defeated Ruadrí Ua Conchobair
in a battle at Ardee and in 1162 led an army against
the Norse of Dublin, who submitted, paying Mac
Lochlainn “six score ounces of gold.” Muirchertach
was a ruthless king. In 1160, he had the influential
Domnall Ua Gairmledaig, lord of Cinél Móen, assas-
sinated. However, in 1166 Muirchertach made a fatal
mistake when he blinded Eochaid Mac Duinnsléibe,
king of Ulaid. This blinding outraged the north of
Ireland, and Mac Lochlainn was abandoned by most
of his army. He was defeated and killed by Mac
Duinnsleibe’s foster-father and guarantor, Donnchad
Ua Cerbaill, king of Airghialla. In his obit, Mac
Lochlainn was called “the chief lamp of the valour,
chivalry, hospitality, and prowess of the west of the
world in his time.”
Following Muirchertach Mac Lochlainn’s death, the
Ua Neills emerged again as a force to be reckoned
with in Tír nEógain and took the kingship from their
Mac Lochlainn rivals. In 1167, the new high king,
Ruairí Ua Conchobair divided Tír nEógain in two,
north and south of the mountain, between Muirchert-
ach’s son, Niall Mac Lochlainn, and Áed “An Maca-
oimh Tóinleasc” Ua Néill. After the Anglo-Norman
invasion of Ulster, the Meic Lochlainn assisted the
Ulaid against John de Courcey. In 1196, Muirchertach
Mac Lochlainn, king of Tír nEógain, was noted as a
“destroyer of the cities and castles of the English.” He
was slain in that year by an Ua Catháin, a member of
a new rising dynasty in County Derry. In 1215, Áed
Mac Lochlainn was killed by the English.
In the early thirteenth century, the Meic Lochlainn
began to occupy the ecclesiastical center of Derry but
were becoming very unpopular among the Cénel
nEógain. In the 1230s, Domnall Mac Lochlainn
became very powerful. In 1235, he killed Domnall
Ua Néill, the king of Tír nEógain, and assumed the
kingship himself. In 1238, Domnall instigated a
Gaelic Irish uprising against Hugh de Lacy, east of
the Bann, and in 1239 he was victorious in the battle
of Carnteel, fought near Dungannon, against some
Ua Néill and Ua Gairmledaig rivals. However, Domnall
was crushingly defeated at the battle of Caimeirge (a
site traditionally said to be near Maghera in Co.
Derry), by Brian Ua Néill and Máelsechnaill Ua
Domnaill, king of Tír Conaill. Domnall and ten other
Meic Lochlainn of his derbhfine(close family) were
killed. The battle of Caimeirge proved to be decisive
in the struggle for power in Tír nEógain between the
Meic Lochlainn and the Ua Néills. Very unusual for
Gaelic Ireland, the Mac Lochlainn family was totally
eclipsed and never again threatened Ua Néill hege-
mony of Tír nEógain. After the battle, Brian Ua Néill
married Mac Lochlainn’s daughter, Cecilia, and a
Mac Lochlainn chieftain, Diarmaid Mac Lochlainn,
was killed at Brian Ua Néill’s great defeat at Down
Patrick in 1260.