• Died: 13 Nov 863

  Research Notes:

He was recognised as king of Tara on the death of his predecessor Niall Caille in 846. King of Tara in Ireland, in 847. 167th High King of Ireland between 847 and 860. He called a great meeting of the chieftains of Ireland to establish peace and concord between the men of Ireland in 857 in Rath Aedha Mic Bric. He led a host of the men of Leinster, Munster and Connaught, and of the southern Ui Neill, into the North, pitching a camp at Magh Dumha, in the vicinity of Ard Macha, where they were attacked by Aedh Finnliath, son of Niall, and Flann, son of Conang, and Maelseachlainn and his army manfully defended the camp in 858 in Ulster, Ireland. He gave battle to the foreigners of Ath Cliath, where many of the foreigners were slain by him, in 859. He was given assistance by Cearbhall, lord of Osraighe, against Aedh Finnliath, son of Niall, and Amhlaeibh, in 859.

[Annals of Ulster 862: "Mael Sechnailll son of Mael Ruanaid son of Donnchad son of Domnall son of Murchad of Mide son of Diarmait the Harsh son of Airmedach the One-eyed son of Conall of the Sweet Voice, son of Suibne son of Colmán the great son of Diarmait the red son of Fergus Wrymouth, king of all Ireland, died on the third feria, the second of the Kalends of December 30 Nov., in the 16th year of his reign. / Mael Sechnaill m. Mael Ruanaigh mc. Donnchadha mc. Domnaill mc Murchadha Midhi mc. Diarmada Den m. Oirmedhaigh Chaeich mc. Conaill Guthbhinn mc. Shuibhne mc. Colmain Moir mc. Diarmada Derg mc. Fergusa Cerrbeoil, ri h-Erenn uile, .ii. kl. Decimbris, .ii. feria, anno regni suo .xui., defunctus est."]

He died during the first year of Constantine I of Scots rule. He died on the thirteenth day of November precisely, on Tuesday, after he had been sixteen years in the sovereignty.