The name Macnab derives from the Gaelic ‘Mac an Aba’, ‘child of the abbot’. According to tradition, the progenitor of this great clan was Abaruadh, the Abbot of Glendochart and Strathearn, the younger son of King Kenneth Macalpine. Abaruadh, the Red Abbot, was descended from King Fergus of Dalriada and a nephew of St Fillan, founder of the monastery in Glendochart in the seventh century.

Robert, the fourteenth chief, was apprenticed to study law under Colin Campbell of Carwhin, and he married the sister of John Campbell, Earl of Breadalbane. This strong Campbell connection constrained him from supporting the Jacobite rising in 1715, although many of his clansmen drew their swords for the ‘Old Pretender’. The fifteenth chief was a Major in the British Army. His brother Archibald was also a serving officer and was taken prisoner by Jacobite forces at the Battle of Prestonpans in 1745.

Francis Macnab succeeded as sixteenth chief, and although within the clan he is renowned as a notable producer and consumer of whisky, he is more generally known as ‘The Macnab’ of Raeburn’s outstanding portrait. He inherited a great burden of debt, and despite considerable personal efforts, he owed over £35,000 when he died in 1816. He had never married, and was succeeded by his nephew, Archibald, who made desperate efforts to extricate the estate from debt. In 1823 a writ of foreclosure was issued, and Archibald was forced to flee to Canada, where he eventually obtained a grant of land in the Ottawa River Valley. Eighty-five settlers came to the estate, which he renamed Macnab. When an official enquiry was threatened into allegations of excessive rents there, he fled to Orkney, then to London, and finally to France, where he died in 1860. Sarah Anne, the eldest of his children, was recognised as the eighteenth chief, but she died unmarried in Italy in 1894.

It was established that the Arthurstone branch of the chiefly family was now entitled to succeed and the de jure chiefship passed to James William Macnab. He served in the East India Company and was succeeded by his eldest son, James Frederick, rector of Bolton Abbey. His only son, James Alexander, succeeded as twenty-first de jure chief. In 1954, he relinquished the chiefship to his uncle, Archibald Corrie Macnab, who had acquired the Killin estate to enable him to become the twenty-second de facto chief. Archibald died in 1970 when the succession reverted to James Charles, the eldest son of James Alexander, who is the present and twenty-third chief.