Saint Mac Nisse was an early Irish saint known as the founder and first bishop-abbot of Connor

Bishop of Connor

The Bishop of Connor is an episcopal title which takes its name after the village of Connor in County Antrim, Northern Ireland. The title is currently used by the Church of Ireland, but in the Roman Catholic Church it has been united with another bishopric....

 (Irish: Condere, in what is now Co. Antrim). In the Tripartite Life of St. Patrick, he is said to have been a disciple of St. Olcán

Olcan

Olcán is the name of an early Irish saint of the Dál Riata, disciple of St Patrick and founder of Armoy in northeast Antrim.-Olcán and the Dál Riata:...

, Bishop of Armoy.

His story as known is largely legendary He is said to have been baptized by Saint Patrick

Saint Patrick

Saint Patrick was a Romano-Briton and Christian missionary, who is the most generally recognized patron saint of Ireland or the Apostle of Ireland, although Brigid of Kildare and Colmcille are also formally patron saints....

. He is considered the founder of Kells monastery, having been at Kells as a hermit. His feast day is 4 September

Primary sources

• Tripartite Life of St Patrick
• Félire Óengusso
• Annals of Ulster
  Annals of Ulster
  The Annals of Ulster are annals of medieval Ireland. The entries span the years between AD 431 to AD 1540. The entries up to AD 1489 were compiled in the late 15th century by the scribe Ruaidhrí Ó Luinín, under his patron Cathal Óg Mac Maghnusa on the island of Belle Isle on Lough Erne in the...
  
  
• Life of St. Nisse (Codex Salmanticensis
  Codex Salmanticensis
  The Codex Salmanticensis is a medieval Irish manuscript containing an extensive collection of Irish saints' Lives, now in the Royal Library of Belgium in Brussels...
  
  ), ed. W.W. Heist, Vitae Sanctorum Hiberniae ex codice olim Salmanticensi nunc Bruxellensi. Brussels, 1965. p. 406. Short, late homily for the saint's festival (3 September) at Connor.