History Files


Gaelic Kingdoms

Kingdoms of Ireland




MapKings of Ulaid (Gaels of Ireland)

The biggest upheaval in Ireland in the period between the fourth to sixth centuries was in the north, where the Uí Neill clan (pronounced e-nay-al) rapidly expanded from their homeland in the west of Ireland. One branch moved to Ulster, where they banished the Ulaid from the cult centre of Navan Fort, and set up the kingdoms of Tyrone and Tirconnell (Donegal). Another section of the family, known as the Southern Uí Neill, moved eastwards across the Shannon to capture the sacral kingship of Tara in the region known as Brega, apparently pushing back the old Laigin tribe to the area south of the River Liffey. From that point onwards, the Northern Uí Neill were also traditionally the high kings of Ireland.

(Additional information by Edward Dawson.)

Northern Uí Neill (Gaels of Ireland)

fl 4th century

Eochaid Mugmedon

Great-great-great-great-grandson of Conn.

Eochaid Mugmedon spawns several dynasties that subsequently rule the provinces of Connacht, Mide, and Ulster into the middle ages. These dynasties are known by the names of Eochaid's four sons, being the Uí Bruin, Uí Fiachrae, Uí Aillil, and Uí Neill (after Niall Noígillach of the Nine Hostages). The latter is one of the most powerful Irish kings of this period, and his descendants, as the kings of Ulster, provide the high kings of Ireland until 1002.

Kings of Ulster (Gaels of Ireland)

379 - 405

Niall Noígillach of the Nine Hostages

Son. Ruled from Tara. First non-legendary High King?

5th century?

The Laigin interest in Tara, the seat of the high kings, 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.

At this time the title of high king (if it exists at all outside of later romantic fiction) is purely a matter of hierarchy. The authority of the Irish kings is determined by how much they rule. Village chiefs are at the bottom, followed by clan chiefs, tribal chiefs, rulers of minor kingdoms, kings of the so-called 'five provinces' (or kingdoms), and finally the high king himself. He is merely the most powerful warrior of his time, the biggest chief, but he does not rule a united Ireland except as at the head of possible coalitions formed in times of need.


Attacks on the south coast of Britain by Niall are best associated with this year. It is Niall who is in effect the dynasty founder of the Uí Niell, who use a descent system to describe themselves which appears in time to be adopted by most of the island. This system replaces the more traditional tribal system to such an extent that the relationships between the earlier tribes and the later kingdoms are largely lost.

507 - 534

Muirchertach macErcae O'Néill/Muiredach

High King. His daughter m Sawyl Penuchel, king of Dunoting.

St Madoc, son of Sawyl Penuchel of The Peak, is educated at the court of his maternal grandfather, King Muiredach of Ulster. It is there that he becomes interested in Christianity, and he later studies under St David (Dewi Sant) at Glyn Rhosyn. After a spell as abbot of Glyn Rhosyn, he returns to Ireland to found several monasteries, including Clonmore, Drumlane, and Ferns.

572 - 581

Báetán macNinnedo O'Néill

Also known as mac Cairill. High King of Ireland.


The Book of Leinster (190a) makes mention of a tale, now lost, entitled Sluagad Fiachna maic Báitáin co Dún nGuaire i Saxanaib, 'The Hosting of Fiachna son of Baitan to Dun Guaire in Saxon-land'. The Fiachna mentioned in the title is a son of Baetan mac Cairill, king of Ulster (died 581). He is a famous warrior who is killed in 626. The Dún Guaire mentioned is the Irish form of the British Din Guayroi, the native name of Bebbanburch (modern Bamborough), the capital of Bernicia.

The Annals of Ulster also mention an event for 623, 'expugnatio Ratho Guali la Fiachna mac Báetáin', 'the storming of Rath Guali by Fiachna son of Baetan'. The details of the event seem to have been lost, but in general terms, an Irish raiding party led by Fiachna, son of Báetán seems to have attempted to storm the Bernician stronghold of Bamborough. Given the fact that the Bernicians had already weathered half a century of similar attacks by Britons, it seems a rather foolish expedition, and it results in Fiachna's death.

1002 - 1014

Brian Boru of Munster

High King.

1014 - 1022

The High Kings of Ireland.

1022 - 1064

Donnchad MacBrian of Munster

High King.

1064 - 1072

Diarmait MacMáil na mBó of Leinster

High King.

1072 - 1086

Toirdelbach O'Brien of Munster

High King.

1090 - 1121

The High Kings of Ireland.

1121 - 1135

Toirrdelbach macRuaidrí na Saide Buide ua Conchobair / Turlogh of Connacht

High King.

1141 - 1150

Toirrdelbach macRuaidrí na Saide Buide ua Conchobair / Turlogh of Connacht

High King.

1150 - 1166

The High Kings of Ireland.

1166 - 1175

Ruaidrí macToirrdelbaig of Connacht

High King.

1175 - 1177

Much of Ireland, including the majority of Ulster by 1177, now falls under the control of the kings of England.