Celestine MacDonald was the eldest son of Alexander of Islay, Earl of Ross, 3rd Lord of the Isles and 8th chief of Clan Donald.
[1] His mother was likely the daughter of Neil or Angus MacPhee of Glenpean in Lochaber, and Alexander may have married her via handfast.
Instead the right remained with his younger brother John of Islay, Earl of Ross, 4th Lord of the Isles, 9th chief of Clan Donald, the son of Elizabeth Seton.
[4] They were superiors under the Lord of the Isles of the lands of Lochiel in Lochaber, in addition to the claims of a close marriage alliance (Ewen married a daughter of Celestine of Lochalsh).
[5] He escaped southward amongst the Isles but was caught on the island of Oransay, by MacIain of Ardnamurchan, and put to death.