Although up to the tenth century, surnames in Ireland were not hereditary, the influence of the church, dating from this period, can still be seen in many common modern Irish surnames, in particular those beginning with “Gil-” or “Kil-“, an anglicised version of the Irish Giolla, meaning follower or devotee. Thus Gilmartin, in Irish Mac Giolla Mhairtin, means “son of a follower of (St.) Martin”. Similarly, the church is the origin of all of those names starting with “Mul-“, a version of the Irish Maol, meaning bald, and applied to the monks because of their distinctive tonsure. Thus Mulrennan (Ó Maoilbhreanainn) means “descendant of a follower of St. Brendan”.