There is a tradition, not borne out, however by any tangible evidence or confirmation, that this very ancient family deduced its descent from a member of the House of Geraldine, in Ireland (whence sprang the noble families of Leinster, Desmond, &c.), who, with a considerable number of his followers, is stated to have settled in Scotland about the year 1261, and to have so powerfully aided King Alexander III, a few years afterwards, in repelling the invasion of Haco, King of Norway, that he was rewarded by a grant of the lands of Kintail, in the County of Ross, which were erected into a free Barony by charter, dated 9th January 1266. Therefore Colin Fitzgerald was the first feudal Baron of Kintail.

His grandson who in the Gaelic was called Coinneach MacCoinneach (Kenneth son of Kenneth), 3rd Baron of Kintail, became corrupted in English into Mackenzie (pronounced: MacKenny) and hence arose all the families of Mackenzie in Scotland. The name "Mackenzie" therefore coming from the Gaelic: "MacCoinneach" meaning: "Son of the Fair One".

Examining records that suggest a descent from the Earls of Ross indicate that such a descent existed through Margaret, the wife of Kenneth A'Blair Mackenzie VIII Baron of Kintail, she was the daughter of John IV Lord of the Isles and Earl of Ross.