Domnall mac Áedo

Domnall mac Áedo (died 642), also known as Domnall II, was a son of Áed mac Ainmuirech. Domnall was High King of Ireland from 628 until his death. He belonged to the Cenél Conaill kindred of the northern Uí Néill.

The year of Domnall's birth is not known, and even an approximation depends on the date of the convention of Druim Cett, which is debated. Certainly he must have been born around 570 at the earliest, and around 590 at the latest. According to Adomnán's Life of Saint Columba, Domnall mac Áedo met Columba at Druim Cett while still a boy. Columba prophesied great success and a peaceful death in old age for Domnall.

Domnall's brother Máel Cobo (died 615) is said to have been High King of Ireland, and his father Áed also, but both claims are later inventions based on the Annals of the Four Masters and similar writings. The list of High Kings found in the Baile Chuinn Cétchathaigh (The Frenzy of Conn of the Hundred Battles), which is dated to before 695, includes Domnall. The original writer of the Annals of Ulster named just twelve "kings of Ireland", starting with Domnall in 628–642, and ending with Ruaidrí Ua Conchobair in 1166–1186.

The first reference to Domnall in the Annals of Ulster is for 628, a report of the battle of Both where Domnall was defeated by the reigning High King, his distant Uí Néill cousin Suibne Menn of the Cenél nEógain. Shortly after, Suibne Menn was killed by Congal Cáech, the Dál nAraidi king of the Ulaid. Later in the year Domnall took his army raiding into Leinster. Success in warfare was the usual test of a new king, and afterwards the Annalists assume Domnall was acknowledged as High King.

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