The first man to take the name “Murchison” was Ian Dubh MacMhurchaidh MacCalman (“Black John son of Mhurchaidh son of Calman”) who was an Episcopal priest at Lochalsh near the Isle of Skye. There he built a stone chapel on a hill above the village of Ardelve, near Eilean Donan Castle . He took the Anglican name John Murchison when he entered the priesthood.

In 1532 a conflict erupted when Donald Gorm MacDonald tried to take control of Eilean Donan Castle by force. During the battle the Constable of the castle was killed, as well as MacDonald, and after the battle a dispute arose between the MacRaes and the MacLennons over who should be the next Constable. This dispute became heated enough that Sir Kenneth MacKenzie (Earl of Seaforth, who owned the Castle and the land) decided that installing either would cause a clan battle, and so he directed John Murchison to become Constable. Murchisons have been the Constable at Eilean Donan off and on ever since.