The accompanying text in 'The Clans of the Scottish Highlands' by James Logan begins as follows: "SIOL AUSLANICH - CLAN BUCHANAN The seanachies, or genealogists of this clan, derive it from Auslan bui', son of O'Kyan, an Irish prince, who came to Scotland in the country of Stirling. It was the usage of the Celts to give distinctive appellations to individuals and tribes from the localities where they might reside, and the district occupied by this clan bears a Gaëlic name. MacAuslan is, however, an original patronymic, which a branch of the clan yet retains, Gillebrid, seneschal to the Earl of Lennox, who flourished 1240, being the first who was styled 'de Buchanan'. His father, MacBeth, obtained a grant of Clâr innis in 1225; but it must be borne in mind that lands were held in undisturbed possession long before the feudal tenure by charter was introduced. Various other grants were, from time to time, made to the lairds of Buchanan, who, up to 1682, when the last chief died without male issue, numbered twenty-two. One of these charters, dated 1564, confirmed possession of both Clareinch and Kepinch, with the bell and alms of St Kessog! A branch of this clan who possessed the lands of Lennie, held them by the preservation of a large sword, with which their ancestor had first acquired them. Whoever had the custody of this weapon, and a tooth of St Fillan, were presumed to have a good right to that estate."