Dictionary of National Biography, 1885-1900/Niall (d.1062)
NIALL (d. 1062), king of Ulidia or Lesser Ulster, was son of Eochaidh and grandson of Ardghar, eighth in descent from Bec Boirche, king of Ulidia in 716. His nephew Niall, son of Dubhtuinne, who was king of Ulidia, was defeated by him in battle and deposed in 1011. In 1015 he was attacked by Maelseachlainn II [q. v.], king of Ireland, and had to yield him hostages. After this defeat the deposed Niall, son of Dubhtuinne, with some of the inhabitants of Dal nAraidhe, the southern sub-kingdom of Ulidia, rose against him; but he defeated them and slew his nephew. To secure his position, in 1019 he blinded his kinsman, Flaibheartach O'Heochaidh. Niall had many ships, and in 1022 defeated a Danish fleet off his coast and captured most of its vessels and their crews. Later in the year he invaded the territory of the Airghialla in the south of Ulster, and won a great victory at Slieve Fuaid, co. Armagh. The Cinel Eoghain attacked him in 1027, and carried off a great spoil of cattle from Ulidia. In 1047 there was so great a famine in his country that many of his people migrated to Leinster. The famine was followed by deep snow from 2 Feb. to 17 March, and the year was long known to chroniclers as ‘bliadhain an mór sneachta’ (‘the year of the great snow’). He died 13 Sept. 1062. His son Eochaidh died on the same day, but left descendants who take their name from him; some of them survive on the coasts of Ulster to this day, and are famous for their skill as boatmen and sea-fishers. They are called after him in Irish O'Heochaidh, which is often anglicised Haughey, and sometimes Haugh, Hoey, or Howe.
[Annala Rioghachta Eireann, ed. O'Donovan, vol. i.; Annals of Ulster, ed. Hennessy, vol. i.; local information.]