The Dullahan is a type of legendary creature in Irish folklore. He is depicted as a headless rider on a black horse, or as a coachman, who carries his own head. As it not widely attested in native sources, including no references to it on the extensive website of the Irish Folklore Commission Dúchas.ie, there is doubt as to whether the Dullahan was originally a part of the Irish oral tradition.
Dullahan, the headless horseman—Illustrated by W. H. Brooke, Croker, Fairy Legends (3rd ed., 1834).