The principal family (Buchanan of that Ilk) held a large estate for over six hundred years in an uniterrupted succession of 22 Lairds.
In the time of John Buchanan (died 1681) the last Laird of Buchanan, the estate was lost, and passed into the hands of the Duke of Montrose - Graham family.

Individual cadet families held land in and around the area for many years thereafter, and still today there are strong connections in the area with the Clan Buchanan.

The name Buchanan comes from the gaelic BOGHCHANAN 'low land belonging to the canon' and BOTHAHANIAN 'the canon's seat. The name obviously points to some connection in early times with the Canon of Inchcailleach.

The Island of Inchcailleach is situated in Loch Lomond off Balmaha, ( the pass to the highlands) and near the mouth of the river Endrick contains the ruins of a church established between 650 and 700 AD by St. Kentigerna, wife of an Irish Prince, Feradach.

The Clan was active in Scotland in early times and supported King Robert the Bruce at Bannockburn.
Claims regarding the origins of the Clan stem from various quarters and of these the principal stories are as follows.
William Buchanan of Auchmar, the generally accepted historian of the Clan Buchanan.

Claims that the origins of the clan stem from 'Anselan o'Cahan ) o'Kyan ) son of the King of Southern Ulster, who was forced to flee his native land because of his involvment in the slaughter of the Danes at Limerick. Anselan arrived in Scotland in 1016 and offered his services to King Malcolm II. So valiantly did he serve the King that he was granted the lands of 'Boghchanan' in Stirlingshire. Tartan illustred is Ancient Buchanan