O'Cahan is the name of a significant clan in Ulster. It has been angiclized to O'Kane and Kane.

There is still a lot of historical evidence of the clan's ancient Ulster roots. These include Dungiven Priory which is reputed to be the tomb of Cooey-na-Gal O'Cahan, who died in 1385. 'Cooey-na-Gal' means "Terror of the Stranger", so the fact that he is lying here rather than stalking the valley is a great relief to the average tourist.

Turlough O'Cahan owned Dunseverick castle in medieval times. Dunseverick was a 'key' ancient site in Ireland and one of the royal roads from Tara, seat of the Kings of Ireland, ended here.