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Gaelic British Isles & Ireland

Tribes and States of Ireland


MapKings of Laigin / Leinster (Gaels of Ireland)
Incorporating the Concani/Gangani

There exists a very small window through which to view the early tribes of Gaelic Ireland (those which largely pre-date the Roman presence in Britain). Ptolemy's Geographia recorded the tribes of Ireland some time in the second century AD, seemingly the first person to do so. Shortly after this, between the second and fourth centuries AD, most of Ireland shifted from tribal naming to descent naming. The shift was so complete by around AD 400 that it is almost impossible to link many of the early tribal names to the later descent names. Within the territory that later formed Leinster dwelt the Concani (or Gangani) tribe.

The Concani appear to have been divided between Ireland and Britain, and in the latter they were called the Gangani. It seems possible that they were a sea-mobile tribe. These had a tendency to travel by water, which would explain their presence in both Ireland and two areas along the coast of North Wales. If they were indeed sea-mobile, there was a good chance they were third wave Celtic arrivals, similar to the Belgic tribes in the south and east of Britain (notably the Atrebates, Belgae, Cantii, and Catuvellauni). Once settled in Ireland, part of the tribe migrated again, to the Lleyn peninsula. It seems that after this, perhaps only shortly before the Roman invasion into the country, the Gangani in Lleyn appear to have divided yet again, with a splinter group heading eastwards. This group came to be known as the Deceangli, and sooner or later they found the Ordovices tribe intruding between them and their brothers in Lleyn. The Concani in Ireland also appear to have migrated again, possibly en masse. They ended up on the west coast by the second century AD, in the later territory of Thomond. This is how both parts of the tribe were ordered and settled when the Romans came across them.

Although no direct link between the first century AD Concani and the later, descent-named 'Laigin' can be proven. Laigin is the older form of Leinster, and it also seems to be the source from which derives 'Lleyn' of the Lleyn peninsula. That may be enough to show at least a tenuous direct link from Concani to Leinster. The '-ster' appendage to the later form of the name is a sign of Danish influence on the Irish from the Viking kingdom in Dublin. Curiously, the presence of Lagore Caibre near the coast, and also Loegaire just above that could be notable. They look remarkably like a slightly different pronunciation of the Welsh word for the English-occupied east of Britain: Lloegr. In Gaelic it seems to come from 'laogh', meaning 'calf', and appears as Early Irish 'lóeg', Welsh 'llo', Cornish 'loch', Breton 'leué', and Middle Breton 'lue'. It can also be found in other Indo-European languages, including Lithuanian and Sanskrit, showing the importance of calves early in history, quite naturally. But could it also be some sort of affectionate term for land in Celtic and Italic? Note that Italy is named after the Itali tribe and their name which refers to a small (young) bull, ie. a bull calf.

From an early date the Laigin had an interest in Tara, the seat of the high kings of Ireland. This probably became a thing of the past when the Southern Uí Neill clan (dominant in Ulster) took over the area known as Brega in which Tara lies, probably in the fifth century AD. In doing this they apparently pushed back the old Leinster descent-named tribe known as the Laigin to the area south of the River Liffey.

(Additional information by Edward Dawson, from Geography, Ptolemy, and from the BBC documentary series, The Normans, first broadcast 4 August 2010, and The Oxford History of England: Roman Britain, Peter Salway.)

3rd century BC

It is likely that the Concani Celts or Belgae arrive in eastern Ireland around this time. The Belgae are migrating en masse into northern Gaul and the Low Countries at this time, while others of their number are diverting to the south-east of Britain. The Concani settle in territory that later becomes part of Laigin.

1st century BC

Elements of the Concani tribe probably migrate to the Lleyn peninsula in Wales from Ireland around this time. They force out the original inhabitants, who may be related to the Ordovices, and quickly split into two bodies. The first settles in the peninsula where retains its name (becoming altered as Gangani), while the second body, perhaps larger in size, migrates eastwards into the area that is now Clwyd and becomes known as the Deceangli. At some point after this, but before the middle of the second century AD, the Concani in Ireland migrate again, ending up on Irelands west coast in the later territory of Thomond.

AD 78 - 79

Fresh from inflicting a final defeat and almost complete destruction upon the Ordovices, the Roman Governor, Julius Agricola, continues his campaign by attacking the warlike Deceangli in Mona (Anglesey). The tribe is duly defeated and for the most part settles down to life under Roman rule. Elements of the tribe apparently flee Britain and find refuge with their possible relatives in Ireland.

5th century?

The Laigin interest in Tara, the seat of the high kings of Ireland, probably becomes a thing of the past when the Southern Uí Neill clan (whose northern kin have become dominant in Ulster) take over the area known as Brega in which Tara lies, probably in this century. In doing this they apparently push back the old Leinster descent-named tribe known as the Laigin to the area south of the River Liffey.

fl 902



FeatureThe combined forces of Leinster and the Southern Uí Neill of Brega expel the Vikings of Dublin. The Vikings are left searching for a new base of operations, which they find in 907 when Æthelred and Æthelflaed of Mercia re-found the city of Chester and settle a Viking army on the Wirral to guard the approach. More Vikings arrive along the Mersey, setting up further colonies and creating the origins of Liverpool (see feature link, right).

1002 - 1014

Leinster is under the direct control of the high kings of Ireland.

1022 - 1064

Leinster is under the direct control of the high kings of Ireland.

1064 - 1072

Diarmait MacMáil na mBó

High King, and king of Dublin (1070-1072).


Died in 1070.

1072 - 1119

Leinster is under the direct control of the high kings of Ireland.


Died in 1115.

1121 - 1135

Leinster is under the direct control of the high kings of Ireland.

? - 1126

Tiorrdelbach Ua Conchobhair


An army is formed by Tiorrdelbach Ua Conchobhair, so he gives the vassal kingdoms of Dublin and Laigin to his own son, Conchobair. Then he marches south to defeat Cormac Mac Carthaigh in battle, before burning his camp at Sliabh-un-Caithligh.

1126 - ?

Conchobair mac Tiorrdelbach


1141 - 1150

Leinster is under the direct control of the high kings of Ireland.

? - 1166

Dermot Mac Murrough

Throne usurped.

1166 - 1170

The kingdom is under the direct control of the High King after Dermot Mac Murrough is forcibly ejected. He flees to Bristol and then Normandy where he gains the support of the English king, Henry II, and Norman allies with which to return to Ireland. The main invasion takes place in 1169 at Bannow Bay with the arrival of the first army of Norman mercenaries to enter Ireland, totalling thirty knights, sixty men-at-arms, and three hundred archers under the Fitzgeralds, marcher lords of Wales.

Leinster is quickly regained following the Battle of Baginbun. A hundred Normans break 3,000 Irish by driving cattle through them to shatter their formation. Then the better armed and equipped Normans slaughter many of the Irish, and take a large number of prisoners from the rest. The Norman commander, Richard de Clare, earl of Pembroke (nicknamed Strongbow), marries Dermot's daughter and is named his heir.

1170 - 1171

Dermot Mac Murrough

Restored. Died the following year.


Richard de Clare 'Strongbow'

Norman son-in-law.


Richard de Clare, earl of Pembroke, or Strongbow, becomes king of Leinster far quicker than expected. This development of Norman lords taking control of Irish kingdoms without being under the authority of the king concerns Henry II of England so much that he arrives to take personal control of what is becoming the invasion of Ireland. He is the first king of England to set foot on Irish shores, arriving with a huge army of 400 ships, 4,000 soldiers, and 5,000 knights. In the event it is a bloodless invasion. The Irish kings know that it is pointless to resist such a vast force. Strongbow also capitulates and his short-lived independence as a Norman king of Leinster is ended. Henry leaves a representative in Ireland to ensure his control and a new colonial mentality is born amongst the Normans. Gerald of Wales subsequently portrays the Irish as being backward and barbaric, ignorant of Christ and of civilisation, thereby justifying the colonisation of Ireland.


Much of Ireland, including Leinster, now falls under the control of the kings of England.

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