UA BRIAIN (UÍ BRIAIN, O’BRIEN)
of Clare to Connacht, driving them to accept Cormac
Mac Cárthaig, king of Desmond, as the king of Munster.
Mac Cárthaig led a coalition of forces from across the
south of Ireland in a prolonged and savage war to
overthrow Ua Conchobair’s hegemony. However,
once the threat from Connacht was ended in 1133 the
Uí Briain ended their alliance with Mac Cárthaig, and
Munster was split in two again. In 1138, Tairrdelbach
Ua Briain, king of Thomond, succeeded in having
Cormac Mac Cárthaig assassinated. Thereafter he
ruled all of Munster until 1151 when another rebel-
lion assisted by Tairrdelbach Ua Conchobair, king of
Connacht, this one led by Cormac Mac Cárthaig’s son
Diarmait, resulted in the province being partitioned
again. The kings of Thomond and Desmond each
looked upon the other as a deadly rival for the kingship
of Munster.
In 1168, Diarmait Mac Cárthaig, king of Desmond,
had Tairrdelbach Ua Briain assassinated in an attempt
to unite Munster under his authority. His ambitions,
however, were thwarted by Ruaidrí Ua Conchobair,
king of Connacht and high king of Ireland, who pre-
ferred to see Munster remain divided and easier to
overawe. Ua Conchobair obliged Mac Cárthaig to
pay an
éraic
(“compensation”) for the killing. Mac
Cárthaig’s assault on Limerick, the capital of
Thomond, early in 1171 failed to advance his aspira-
tions for the kingship of Munster for the same reason.
Indeed, Domnall Mór Ua Briain, king of Thomond,
had aspirations of his own for the kingship of Munster,
and he formed an alliance with Ua Mathgamna
(O’Mahony), one of Mac Cárthaig’s chief subordi-
nates, in a plan to invade Desmond in October 1171.
Coincidentally, Henry II, king of England, had just
landed in Ireland in order to assert his authority over
some Anglo-Norman adventurers (they knew them-
selves simply as “English”) led by Richard de Clare,
earl of Pembroke, better known as Strongbow. Mac
Cárthaig submitted to Henry II in a bid to avoid the
planned Ua Briain invasion, prompting Domnall Ua
Briain and Ua Mathgamna to do likewise. Impressed
by the alacrity with which the kings in Ireland were
willing to submit to him, Henry II decided to revive
the papal grant of Ireland to him in the privilege known
as
Laudabiliter
.
Anglo-Norman Invasion
Limerick was captured by Anglo-Norman or English
adventurers in 1175, but its occupation was short-lived.
In 1177, Henry II granted the Ua Briain kingdom of
Thomond and the Mac Cárthaig kingdom of Desmond
to three of his leading knights. Domnall Ua Brian
managed to repulse Philip de Braose, the grantee of
Thomond, at the walls of Limerick and save Thomond
from invasion. By contrast, the unwalled town of Cork
fell easy prey to its grantees and became the center of
a new English colony in southern Ireland. Ua Briain
took advantage of Mac Cárthaig’s discomfiture by
invading Desmond late in 1177. Ua Briain’s efforts
failed, but they were instrumental in forcing Mac
Cárthaig to temporize with the English and concede a
large part of his kingdom to them.
Domnall Ua Briain’s strategy in dealing with the
English thereafter was to continue to offer robust resis-
tance while showing a willingness, nonetheless, to
reach an accommodation with the English crown in
order to safeguard as much as possible of his king-
dom. When the Lord John came to Ireland in 1185,
Ua Briain, together with Ruaidrí Ua Conchobair of
Connacht and Diarmait Mac Cárthaig of Desmond,
submitted to the prince, but the Irish kings were treated
with open contempt and derision. John granted north-
eastern Thomond to Theobald fitz Walter, ancestor of
the future Butler earls of Ormond, and he granted
much of southeastern Thomond to Philip of Worcester
and William de Burgh. Ua Briain offered stout resis-
tance to the invaders, and it was only following his
death in 1194 that the English were able to consolidate
their control of Ormond and capture the capital of
Thomond, Limerick. John granted Limerick the status
of a royal borough around 1197, and he gave away
much of the Ua Briain lands in Limerick diocese to
the sons of Maurice fitz Gerald, ancestor of the future
earls of Desmond.
Donnchad Cairbrech Ua Briain (
c.
1242), the next
strong king of Thomond, concentrated his efforts on
safeguarding the Uí Briain heartland in Clare from
English incursions. He reached an accommodation
with King John wherein he accepted a knighthood and
committed himself to paying a substantial rent to the
English crown for his diminished kingdom. It was a
strategy that largely succeeded, though there were
lesser Uí Briain who dissented from his policy of
collaboration with the English.
Conchobar, Donnchad’s son and successor, con-
tinued his father’s strategy, but from 1248 Henry III,
king of England, made grants resulting in English
colonization in and around Bunratty. When the
English sought to make further inroads into Thomond,
Conchobar fought back hard and routed an English
force sent against him in 1257. In the following year
his son Tadc Ua Briain met with Áed Ua Conchobair,
king of Connacht, and Brian Ua Néill, king of the Irish
of Ulster, at Cáel Uisce to agree to the formation of a
national confederacy against the English. The confed-
eration proved to be short-lived, however. Tadc died
in 1259, and Ua Néill was killed soon afterward. The
Irish were too divided among themselves, and too weak