UÍ NÉILL, SOUTHERN
center of Ireland from north County Dublin to north-
eastern Connacht.
During the earliest period of recorded history, the
fifth and sixth centuries, the dominant branches of the
Southern Uí Néill were the descendants of three puta-
tive sons of Niall Noígiallach: Lóegaire (Cenél
Lóeguiri), Coirpre (Cenél Coirpri) and Fiachu (Cenél
Fiachach). Cenél Lóeguiri had their base near the
church of Trim in County Meath and controlled large
tracts of land from Lough Erne in the north to Rathlihen,
near the Slieve Bloom mountains, in the south. Many
historians have concluded that, from the earliest his-
torical period, Cenél Coirpri extended from its base
in northeast Connacht to the northern borders of
Leinster. It is more probable that the primary Coirpre
kingdom was in northeastern Connacht and that the
incursion by one branch into northern Tethbae (County
Longford), where a separate kingdom was estab-
lished,occurred as late as the eighth century, while
Cenél Coirpri settlement on the Mide–Leinster borders
only occurred in the mid-twelfth century, although they
had made incursions into Mide before that time. Cenél
Fiachach were located in the territory around Uisnech
(the traditional center point of Ireland). The earliest
list of the kings of Tara, Baile Chuind, includes the
names of Lóegaire and his son Lugaid, as well as
Coirpre and his grandson Tuathal Máelgarb. The his-
tory of these early groups is closely associated with
the struggle to wrest the northern midlands from the
Laigin.
By the mid-sixth century, a branch of Uí Néill
claiming descent from Conall Cremthainne mac
Néill had assumed a dominant position. Diarmait
mac Cerbaill (d. 565) was the first of that line to
become over king of the Uí Néill. Two sons of Diarmait,
Áed Sláine and Colmán, were the ancestors of the
two major dynasties that dominated the Southern Uí
Néill from the seventh century onward, viz. Síl
nÁedo Sláine and Clann Cholmáin. Originally these
groupings were based in Brega (modern County
Meath along with north County Dublin and south
County Louth). During the seventh and early eighth
centuries, the Síl nÁedo Sláine were in the ascen-
dant, and several of their number became over kings
of the Uí Néill during this period. Among these,
Fínsnechta Fledach (d. 695) was perhaps the most
notable. He is remembered in later tradition as the
king who remitted the Bóruma(“the Cattle Tribute”)
that the Laigin had to pay to the Uí Néill. By the
middle of the eighth century, Síl nÁedo Sláine had
divided into northern and southern branches. The
northern branch, which assumed the name Ciannachta—
after the people whose lands they had appropriated—
were centered on Knowth; the southern branch was
based at Lagore.
The Emergence of Clann Cholmáin
Clann Cholmáin, which had hitherto been largely sub-
ordinate to their Síl nÁedo Sláine cousins, began, dur-
ing the first half of the eighth century, to assume a
position of power in the territory to the west of Brega
that was to become the kingdom of Mide. From 728
onward, Clann Cholmáin excluded Síl nÁedo Sláine
from the over kingship of the Uí Néill for some two
hundred years.
It was during the reign of Donnchad Midi that Clann
Cholmáin became a dynasty of national importance.
Donnchad succeeded in subduing Leinster and the
Northern Uí Néill and sought to control Munster as
well. Much of his reign was, however, taken up with
attempting to subdue the Ciannachta branch of Síl
nÁedo Sláine. Donnchad’s death, in 797, was followed
by a period of limited achievement for Clann
Cholmáin.Ninth and Tenth Centuries – The Era
of Clann Cholmáin Dominance
Máel Sechnaill I mac Máele-Ruanaid advanced the
cause of Clann Cholmáin further in the mid-ninth cen-
tury. His obituary in the annals, for the year 862,
describes him as rí Hérenn uile (“king of all Ireland”).
The claim is somewhat inflated; while he achieved a
significant level of dominance over most of the major
dynasties and some notable victories over the Vikings,
he faced persistent opposition from the Ciannachta and
from Áed Findliath of Cenél nEógain. The reign of
Máel Sechnaill’s son, Flann Sinna (“Flann of the Shan-
non”), enjoyed a remarkably lengthy reign as king of
Tara; when he died in 916, he had held the kingship
for thirty-seven years. Flann achieved a reasonable
measure of military dominance throughout this career,
but, not too surprisingly, he faced the growing unrest
of his ambitious sons who challenged him on a number
of occasions. However, it was as a patron of the church—
and, in particular, the monastery of Clonmacnoise—
that Flann is best remembered. He built Tempul na Ríg
at Clonmacnoise in 909, and his patronage of the mon-
astery is commemorated by an inscription on the Cross
of the Scriptures.
The emergence of Congalach mac Máel-mithig of
Síl nÁedo Sláine as over king of the Uí Néill in 944
represented a break in the two-hundred-year-old
convention whereby the kingship alternated between
Clann Cholmáin and Cenél nEógain (see Uí Néill).
The accession of Congalach, who was something of a
compromise candidate, was made possible by the com-
plex political circumstances within the Uí Néill
dynasty arising from the reemergence of Cenél Conaill
as a significant force within the Northern Uí Néill.