Finley Family History. This is a Scottish surname, which is also found widely in Ireland. The spellings recorded range widely from the original Gaelic "Fionlagh" and include Findlay, Finely, Finelly, Finelay, Fennelly, Finlry and Finlray. However spelt it is composed of the original elements "fionn" meaning "fair", plus "lagh", a hero.