The Barons of Gourock were descended from the McIllreich of Jura. Duncan Darroch who had been born on Jura, probably in the early 18th century, settled in Jamaica. There he amassed a considerable estate and prospered. However he was determined to return to his native soil and in 1784 acquired the lands and barony of Gourock from the Stewarts of Castlemilk. He was designated "Chief of that ancient name the patronymic of which is McIllreich" by the Lord Lyon King of Arms.