Niall Noígíallach (ˈniːəl noɪˈɣiːələx, Old Irish "having nine hostage

Hostage

A hostage is a person or entity which is held by a captor. The original definition meant that this was handed over by one of two belligerent parties to the other or seized as security for the carrying out of an agreement, or as a preventive measure against certain acts of war...

s"), or in English, Niall of the Nine Hostages, son of Eochaid Mugmedón

Eochaid Mugmedon

-Biography:According to medieval Irish legend and historical tradition, Eochaid was a High King of Ireland, best known as the father of Niall of the Nine Hostages and ancestor of the Uí Néill and Connachta dynasties...

, was an Irish

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 king, the eponym

Eponym

An eponym is the name of a person or thing, whether real or fictitious, after which a particular place, tribe, era, discovery, or other item is named or thought to be named...

ous ancestor of the Uí Néill

Uí Néill

The Uí Néill are Irish and Scottish dynasties who claim descent from Niall Noigiallach , an historical King of Tara who died about 405....

 kindred who dominated Ireland from the 6th century to the 10th century. The rise of the Uí Néill dynasties and their conquests in Ulster

Ulster

Ulster is one of the four provinces of Ireland, located in the north of the island. In ancient Ireland, it was one of the fifths ruled by a "king of over-kings" . Following the Norman invasion of Ireland, the ancient kingdoms were shired into a number of counties for administrative and judicial...

 and Leinster

Leinster

Leinster is one of the Provinces of Ireland situated in the east of Ireland. It comprises the ancient Kingdoms of Mide, Osraige and Leinster. Following the Norman invasion of Ireland, the historic fifths of Leinster and Mide gradually merged, mainly due to the impact of the Pale, which straddled...

 are not reliably recorded but have been the subject of considerable study and attempts to reconstruct them.

Although generally supposed to be a historical personage, very little can confidently be said of Niall's life.