Mac Craith (Meic Craith, collective form), Irish surname, one branch of which is rendered McGrath.Other branches are rendered McCragh, Crah, Crow, Crowe and many alternative forms which link the MacCraith name back to the ancestral name MacConcrada. These names are all linked by DNA as Irish Type III. When haplotypes with these definitive markers are studied, it is found that the surnames, O'Brien/Bryant, Hogan, Kennedy, Casey McGraw/McGrath and Crow(e) are seen frequently. DNA-based research has revolutionised the traditional understanding of name derivation.
There were at least two distinct families named Mac Craith in medieval Ireland.
The Meic Craith of Thomond were a learned family who had close ties to Clare Abbey, an Augustinian foundation. They were historians and poets attached to the Uí Bhriain kings and earls of Thomond.
Another family of the name, not known to be related, were natives of Termon McGrath, Lough Erne.
Members of the Thomond family recorded in the Irish annals included
Other notable members of the family include