Duffy, Seán. “Irishmen and Islesmen in the Kingdoms of Dublin
and Man, 1052–1171.” Ériu, 43, (1992), 93–133.
Kinsella, Stuart. “From Hiberno-Norse to Anglo-Norman,
1030–1300.” In Christ Church Cathedral Dublin: A History,
edited by Kenneth Milne, 25–52. Dublin: Four Courts Press,
2000.
Mac Shamhráin, Ailbhe. “The battle of Glenn Máma, Dublin,
and the high-kingship of Ireland: a millennial commemora-
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See also Amlaíb Cuarán; Christ Church Cathedral;
Pilgrims and Pilgrimage; Waterford
SLAVES
Slavery may be characterized negatively by an absence
of judicial status, meaning that the slave was consid-
ered by law to be an object in a slave-owner’s posses-
sion rather than as a person in his or her own right. Status
as a slave might be temporary or permanent, and
although the actual procedures are not known, a slave
could obtain status as a free person. There were three
sources of recruitment for slaves: (1) prisoners of war,
(2) debt slaves, and (3) children born of slaves. Medieval
Irish sources for slavery are abundant but often treat
the subject cursorily and non-systematically. A full pic-
ture of Irish slavery must therefore remain impression-
istic in character.
The most common names for slaves in Irish were
mug for male and cumal for female slaves. Cumal was
also widely used as a unit of value for cattle and land.
“Martyrologies” often refer to slave labor as an image
of personal debasement. The vita of St. Senan tells of
the men of Corcu Baiscind who were admonished to
obey St. Senan to not suffer such hunger that “a man
would sell his son and daughter in distant territories
for nourishment.” A vita of the ninth century relates
that St. Ciaran, a slave to the king, had to grind the
grain every day. Slaves are never associated with hus-
bandry but mainly with heavy agricultural labor such
as sowing, harrowing, thrashing, and grinding.
Ship raids on Britain in the fifth century after the
collapse of the Roman Empire provided prisoners of
wars who were treated as slaves. These raids seem to
have ceased as a result of the stabilization of Britain
in the seventh century. Children born of these prisoners
continued to be a source of an Irish slave population,
although they are rarely mentioned in the idealistic
status system depicted by early medieval Irish laws.
Recurring mention of the sale of children in hunger
years attests to the existence of “debat-slavery” as an
institution throughout the early Middle Ages.
The effect of the Viking attacks and subsequent set-
tlements was to accentuate slavery as a social institution.
Viking warfare did not respect the sanctity of monas-
teries and brought about a change in the norms of
warfare, which included an acceptance to reduce pris-
oners of war to slave status. The Irish annals record
23 instances when Vikings took prisoners en masse,
which must be taken as an indication of slaving oper-
ations. While hostages for tribute were termed géill, the
annals refer to these prisoners as brat (captives). The
early instances of Viking slave raids do not, however,
indicate large-scale operations for a full-blown slave
market, but rather seem to be spectacular acts of defi-
ance and humiliation against the enemy. After the bat-
tle of Tara in 980, the king of Meath is reputed to have
freed all the Irish slaves of Dublin, an act that was
repeated by Brian Boru’s and Máel Sechnaill’s joint
action on Dublin after the victory over Leinster and
the mercenaries of Dublin in 999. During the first half
of the tenth century, slaves were still a by-product of
a particular kind of war, namely retaliatory actions and
military adventures designed to vaunt the capabilities
of the would-be successor. Overall, there is no evi-
dence to suggest that the institution of slavery in Ire-
land and even in Dublin was anything more than a
marginal phenomenon of luxury for the nobles.
However, in connection with the heavy expendi-
tures caused by the struggle for the kingship of Ireland
in the early eleventh century, Irish kings began taking
captives in large numbers. In the decisive campaigns
up to 1014, punitive actions seem to have greatly
increased. The Cenél nEógain king Flaithbertach was
the leading slaver in a number of actions on neighbor-
ing territories. In 1011, he united with the son of Brian
Boru and allegedly took many cows and 300 captives
(brait, a word hitherto restricted to Viking assaults)
from the Cenél Conaill, and the following year he is
credited with the largest booty any king had taken of
captives and kine from the Ulaid. In later years, the
annals repeatedly note the massive taking of prisoners,
and more mundane events were changed by new atti-
tudes to the defeated. Irish warfare had traditionally
seen many plain raids that were not part of a larger
political scheme but rather must be seen as seasonal
traditional manifestations of the bravado of young war-
riors. This long-established custom was called crech,
a prey or a raid for cattle. By the mid-eleventh century,
the taking of captives also became part of these hero-
ics. The rising power of the Northern over kings is
marked in the annals by heavy exactions upon neighbor-
ing kingdoms. The Ua Conchobair kings of Connaught,
who were at times near achieving total supremacy over
Ireland, also practiced the new kind of warfare in their
campaigns. The climax came in 1109, when Muirchert-
ach of the Dál Cais mustered a large force against the
Uí Briúin of Connaught and took many captives from
the islands of Loch Oughter. The Uí Briúin took revengeSITRIUC SILKENBEARD