Geoghegan

Geoghegan (Irish: Mac Eochagáin) is a surname of Gaelic Irish origin.

Often spelt without the prefix "Mac", the name has many variants, including Gehegan, Geoghan, Geohegan, Gahagan, Gagan, and Gagon which approximate the most common pronunciations of the name. It is usually pronounced gay-gan, ge-heg-an or go-hee-gan. In Irish it is Mac (or Mag) Eochagáin, from Eochaidh. The initial "G" of Geoghegan comes from the prefix Mag, a variant of Mac and the anglicised form Mageoghegan was formerly much used.

The sept of the MacGeoghegans is of the southern Uí Néill, and said to be descended from Niall of the Nine Hostages. Niall was alive from the mid 4th century into the early 5th century. His father was Eochaidh Muigh-Medon, of the line of Erimhon, one of the sons of Esbain who it is said took Ireland from the Tuatha de Danann.

Niall's mother was Carthann Cas Dubh, daughter of the king of Britain. Niall's first wife was Inné, mother of his son Fiachu mac Néill, from who the Geoghegans are said to be descended. He also had seven other sons with his second wife, Roighnech. Niall's ancestry is claimed by Irish myth to trace back to Miledh of Esbain, King of Spain, whose wife was the daughter of the Egyptian Pharaoh Nectonibus.. From there the line is sometimes traced to Niul who was married to the daughter of Pharaoh Cingris.

As High King of Ireland, Niall reigned from the ancient Irish royal seat at Tara, in modern County Meath. During his reign he conquered all of Ireland. He took a royal hostage from each of the nine kingdoms he subjugated, hence his famous nickname. He gave each of his sons a territory to govern. Fiachu was given a large area in the midlands. His descendants were known as Cenel Fiachaigh, anglicised at Kenaleagh and their territory was known by that name until Elizabethan times when it became the "Barony of Moycashel", County Westmeath.

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