 The McGillivrays had traditionally held the Dunmaglass estate since the fourteenth century, and William's grandfather was a first cousin of the Chief of Clan McGillivray, Captain William McGillivray of Dunmaglass.However, on his side of the family the land had dissipated so that William's father was a small tenant on what had become part of the Lovat estate, and he was unable to provide secondary schooling for William and his brothers Duncan and Simon.When William's uncle, Simon McTavish, visited from Montreal in 1776, he paid for the education of the McGillivray boys and in 1784 brought William out to Canada to work for him in the North West Company, with an annual salary of £100.