TheConnachta are a group of medieval Irishdynasties who claimed descent from the legendaryHigh KingConn Cétchathach (Conn of the Hundred Battles). The modern westernprovince ofConnacht (IrishCúige Chonnacht, province, literally "fifth", of the Connachta) takes its name from them, although the territories of the Connachta also included at various times parts of southern and westernUlster and northernLeinster. Their traditional capital wasCruachan (modernRathcroghan,County Roscommon).^[1]

The use of the wordcúige, earliercóiced, literally "fifth", to denote a province indicates the existence of a pentarchy in prehistory, whose members are believed to have been population groups the Connachta,^[2] theUlaid (Ulster) and theLaigin (Leinster), the region of Mumu (Munster), and the centralkingdom of Mide. This pentarchy appears to have been broken up by the dawn of history in the early 5th century with the reduction of the Ulaid and the founding of new Connachta dynasties which expanded north and east.

Medieval Irish historical tradition traces these dynasties to the four or five sons ofEochaid Mugmedon:Brion,Ailill,Fiachrae, Fergus Caech (perhaps a literary addition), andNiall of the Nine Hostages. Four were ancestors of new Irish dynasties; those of Brión (theUí Briúin), Fiachrae (theUí Fiachrach) and Ailill (the Uí Ailello, later replaced byUí Maine^[3]) were known asteóra Connachta, or the historicalThree Connachta of the province itself; that of Niall, theUí Néill, at first surpassed its parent dynasty, establishing or continuing the so-calledHigh Kingship of Ireland atTara, and became the most powerful dynasty in Ireland down to early modern times.

However David Sproule points out that:

It does not seem that the word "Connacht" can originally have meant 'the descendants of Conn'; it may have meant 'headship' or 'supremacy' from "cond" or "conn", head, and later have been interpreted as meaning "the descendants of Conn",Conn Cetchathach being derived from the word "Connacht" rather than vice versa. ... the name "Eoganacht" and "Ciannacht" were formed in imitation ...^[4]

Sproule'shypothesis has been accepted by historians such as Paul Byrne.^[5]

The dynasties of theAirgíalla, and through them theUí Maine, while also counted as belonging to the Connachta by medieval genealogists,^[6][7] may not possibly be related, as some have assessed that they descend from other peoples later added to the genealogical scheme.^[8] Regardless, the connections toUí Maine with each of the septs and theirdefined ancestor have been maintained for well over a millennium.

In the sagas of theUlster Cycle, the Connachta, ruled from Cruachan by their kingAilill mac Máta and their formidable queenMedb, are the enemies of theUlaid, ruled fromEmain Macha (Navan Fort,County Armagh) byConchobar mac Nessa, and their wars, notably theTáin Bó Cúailnge (cattle raid ofCooley), are the setting for most of the stories. These sagas are traditionally set around the time of Christ, which creates an apparent anachronism: the Connachta are supposedly named after Conn Cétchathach, who in the usual chronological scheme established by theLebor Gabála Érenn, lived in the 2nd century AD.^[9] Later texts used the supposedly earlier names ofCóiced Ol nEchmacht (the province of the Fir Ól nÉcmacht, an ancient people of Connacht) andCóiced Genaind (the province ofGenann, a legendary king of theFir Bolg)^[10] for the western province to get around this difficulty. However, the saga tradition is older than the chronological scheme, which is an artificial attempt by Christian monks to synchronise native traditions with classical and biblical history, and it is possible that the Ulster Cycle is based on historical wars between the Ulaid and the Connachta which have been chronologically misplaced.^[11]Kenneth H. Jackson estimated that Ulster heroic saga originated in the 4th century.^[12]

• Kings of Connacht
• Síol Muireadaigh
• Cenél Conaill
• Cenél nEógain
• Irish nobility
• Irish royal families

• R-M222 Haplogroup Project atFamily Tree DNA

• Connachta
• Medieval Irish people
• Gaelic-Irish nations and dynasties
• Irish royal families
• Ulster Cycle

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