Comprehensive 1894 study. The clan Mackenzie at one time formed one of the most powerful families in the Highlands. It is still one of the most numerous and influential, and justly claims a very ancient descent. But there has always been a difference of opinion regarding its original progenitor. It has long been maintained and generally accepted that the Mackenzies are descended from an Irishman named Colin or Cailean Fitzgerald, who is alleged but not proved to have been descended from a certain Otho, who accompanied William the Conqueror to England, fought with that warrior at the battle of Hastings, and was by him created Baron and Castellan of Windsor for his services on that occasion.