UA CATHÁINArmagh to make a circuit of Munster and to take away
a stipend and gifts. Tairrdelbach was among those who
petitioned Archbishop Lanfranc of Canterbury to con-
secrate Gilla Patraic as bishop of Dublin in 1074. Gilla
Patraic praised Tairrdelbach’s good government to
Lanfranc. In 1082, a bishop from Tairrdelbach’s home
ofDál Cais corresponded with Lanfranc. Pope Gregory
VII wrote to Tairrdelbach and urged him to support
church reform.
Tairrdelbach’s empire began to show signs of strain
two years before his death. In 1084, Donn Sléibe began
his own empire building when Donnchad Ua Ruairc
of Bréifne submitted to him at Drogheda. In response,
Tairrdelbach led his forces against Ua Ruairc and, with
his sons Tadc and Muirchertach, ravaged Bréifne. Ua
Ruairc moved south—destroying churches in Dál
Cais—and east—raiding the lands around Dublin. At
this time the men of Mide rose in revolt, and the
northern Uí Néill raided Ulaid. Tairrdelbach’s troops
put down the rebellion in Meath. On October 19, Tadc
and Muirchertach defeated an invading Connacht army
at Monecronock; among the slain was Donnchad Ua
Ruairc.
In 1085, Tairrdelbach had the first attack of his fatal
illness when his hair fell out. He died at the age of
- Historians have not regarded his career as favor-
ably as that of his illustrious grandsire, but in some
respects it was more notable. Tairrdelbach dominated
Irish affairs for a longer period, and he died peace-
fully, with his enemies cowed. Able to adapt to
change, Tairrdelbach’s hold on the important Viking
commercial centers reflected the increasing financial
demands that princes throughout Europe were facing.
This sophistication is reflected in the Book of Rights,
a treatise on stipends and dues. Tairrdelbach was more
than just a political being. While not hesitating to
bribe one day and attack the next, as with Aed Ua
Conchobhair, he was unfailingly loyal to his foster-
father Diarmait, even when he had become the more
powerful party. Tairrdelbach’s career shows the prob-
lems and opportunities faced by princes throughout
late-eleventh-century Europe.
BENJAMIN HUDSON
References and Further Reading
Mac Airt, Sean. The Annals of Inisfallen. Dublin: Dublin Insti-
tute for Advanced Studies, 1951.
Ó Corráin, Donncha. Ireland before the Normans. Dublin: Gill
& Macmillan, 1972.
Ryan, John. “The O’Briens in Munster after Clontarf.” North
Munster Antiquarian Journal2 (1941), 141–153; 3 (1942–43),
1–52 and 189–202.
See alsoDal Cais; Jews in Ireland; Kings
and Kingship; O Brien
UA CATHÁIN
The Ua Catháin (later Anglicized O Cahan, eventually
O’Kane) lineage (like the Uí Neill, a branch of the
Cenél nEógain) first appear in the annals in 1138, when
they were already rulers of the territories of Fir na
Craíbe, Fir Lí, and Ciannachta, forming most of the
northern part of the present County Derry. The south-
ward shift of the center of power in Tír nEógain fol-
lowing the final replacement of the Meic Lochlainn by
the Uí Neill as kings after 1242 was to favor their rise
to independent status, as was their cooperation with
elements within the Ulster colony. Although Magnus
Ua Catháin and fourteen others of his lineage fell
fighting against the colonists with Brian Ua Neill at
the battle of Down in 1260, his son Cú Muige (later
called from this circumstance Cú Muige “na ngall,”
“of the foreigners”) was immediately made chief by
Sir Henry de Mandeville, seneschal of Ulster, against
the claims of a rival. Thereafter he remained Sir Henry’s
ally in his struggle against his fellow colonists in
Ulster. Subsequently the Uí Chatháin seem to have
cooperated with Richard de Burgh, the “Red” earl of
Ulster (to whom they paid an annual tribute of forty
cows), and in 1312 Cú Muige’s son, Diarmait Ua
Catháin, styling himself “king of Fir na Craíbe” sur-
rendered to the earl the territory of Glenconkeen (in
the southeast corner of County Derry), which the earl
immediately regranted to Henry Ua Néill, ancestor of
the Clann Áeda Buide. After the collapse of the earl-
dom, the Uí Chatháin became again vassals of the
O’Neills, the most powerful and most refractory, with
intervals (in the early fifteenth and early sixteenth cen-
turies) when they were forced to submit to the control
of the aggressively expansionist Uí Domnaill of Tír
Conaill. The uneasy relationship between the Uí Neill
and the Uí Chatháin, the former seeking to maximize
their control, the latter to minimize it, was to reach its
climax after 1603, in the few years before both were
destroyed by the Plantation of Ulster.
KENNETH NICHOLLSReferences and Further Reading
McCall, Timothy. “The Gaelic Background to the Settlement of
Antrim and Down, 1580–1641.” Unpublished MA thesis,
Queen’s University, Belfast, 1983.
MacNeill, T. E. Anglo-Norman Ulster: The History and Archae-
ology of a Medieval Barony. Edinburgh, 1980.
Nicholls, Kenneth. Gaelic and Gaelicised Ireland in the Middle
Ages. 2nd ed. Dublin, 2003.
Simms, Katharine. “Late Medieval Donegal.” In Donegal His-
toryand Society, edited by William Nolan, Liam Ronayne, and
Mairead Dunlevy, pp. 183–201. Dublin, 1995.
Simms, Katharine. “Tír Eoghain ‘North of the Mountain.’” In
Derry and Londonderry: History and Society, edited by Gerard
O’Brien and William Nolan, pp. 149–174. Dublin, 1999.