Maelsuthain O'Carroll

Maelsuthan Ua Cerbhail, Maelsuthain O'Carroll, or Maelsuthain O'Cearbhail (d. 1010) was a political and academic figure in medieval Ireland. He was lord of the Eóganacht Locha Léin, advisor to High King Brian Boru, and an important scholar often credited for beginning the Annals of Innisfallen. Maelsuthan's academic reputation was considerable, earning him accolades like "chief doctor of the Western world in his time" and "sage of Ireland."

Maelsuthan was a chief of the Eoghanacht of Loch Lein, a branch of a powerful southern Irish tribe that settled around the Lakes of Killarney. He likely received his early education at the monastery on the island of Innisfallen and later became the school's head. There he oversaw the future king Brian's education at the monastery. Maelsuthan began his relationship with Brian Boru as a tutor, but Brian went from pupil to royal and Maelsuthan became his anmchara (an advisor a confessor). After Brian won the high kingship, he went on a triumphal tour throughout Ireland. To secure the backing of the Church, he stopped in Armagh where he laid twenty ounces of gold on the altar of the cathedral and recognised the supremacy of Armagh over the other churches of Ireland. Maelsuthan accompanied the king during the trip (but this is contested by Denis Casey-[2]) and documented the royal donation in the Book of Armagh.

St. Patrick, when going to heaven, ordained that all the fruit of his labour, as well of baptisms, as of causes and other alms, should be carried to the apostolic city, which in Irish is called Ardd-Macha. So I have found it in the libraries of the Scots. This I have written, that is, Calvus Perennis, in the sight of Brian, Emperor of the Scots, and what I have written he determined for all the kings of Maceria.

In the passage, still extant in Maelsuthan's own handwriting, Maelsuthan refers to himself as "Calvus Perennis" a translation of "ever-bald," the meaning of his Gaelic name. Maelsuthan also refers to "Maceria," the Latin for Cashel.

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