The New York Times's theatre critic George Jean Nathan wrote that Lerner's book was based on a much older German story by Friedrich Gerstäcker, later translated by Charles Brandon Schaeffer, about the mythical village of Germelshausen that fell under a magic curse.[6] However, Lerner denied that he had based the book on an older story, and, in an explanation published in The New York Times, stated that he didn't learn of the existence of the Germelshausen story until after he had completed the first draft of Brigadoon.[7][8] Lerner said that in his subsequent research, he found many other legends of disappearing towns in various countries' folklore, and he pronounced their similarities "unconscious coincidence".[7]
Lerner's name for his imaginary locale was probably based on a well-known Scottish landmark, the Brig o' Doon (Bridge of Doon). Other sources suggest that the fictional village's name was constructed from the Celtic word "briga", which means "town" (such as in the old city names of Segobriga and Brigantium) and the Scottish Gaelic "dùn", which means a fort. The name may also be a reference to the Celtic goddess Brigid.