"The name [Campbell] appears to derive from the Gaelic "Cam Beul", meaning Crooked Mouth; while those who bear it are called Clan Diarmaid as the supposed descendants of the handsome Ossianic hero with whom the wife of Fingal fell in love.
"In revenge, Fingal challenged Diarmaid to slay the wild boar that harried the neighbourhood, and then to measure its carcass against the lie of its bristles, with his bare feet. A bristle pierced Diarmaid's Achilles heel, and Fingal refused him a draught of his healing cup as Diarmaid lay dying.
"Scotland's supreme interpreter of Gaelic song, J. C. M. Campbell, is among those who have left a recording of this ballad."
Taken from: "Scottish Clans and Tartans," Dr. Ian Grimble, 1973