The Mackenzies were of Celtic stock and were not among the clans that originated from Norman ancestors. They are believed to be related to Clan Matheson and Clan Anrias, all three descending from the 12th century Gill'Eòin of the Aird. Based initially in Kintail, the clan was recorded at Eilean Donan on Loch Duich, a stronghold with which it was for many centuries associated.