This was very satisfactory because it enabled the Scots, who were only one of the peoples of Scotland, alongside Picts and Britons, and indeed comparatively recent arrivals from Ireland, to take possession of the whole history of Scotland. Lists of kings (all imaginary, dating from Fergus, son of Feuchar) were produced as evidence of this antiquity. In this way, the Scots established their right to independence, disproving the claims of English kings, notably Edward I, to sovereignty over Scotland.
Then Buchanan, drawing on the inventive pseudo-histories of his predecessors, John of Fordoun and Hector Boece, put the myth to immediate political purpose by demonstrating, to his own entire satisfaction, that the Scots had made a habit of deposing any of these kings who proved unsatisfactory. This justified the deposition of Mary Queen of Scots, whom he had come to hate, and was subsequently to prove immensely useful, Trevor-Roper says, to English Whigs in the 17th century.