O Griobhta (pronounced O Greefa) is one of the many Gaelic surnames which have assumed in their anglicized forms those of British families of somewhat similar sound: in this case the earlier O'Griffy has been almost entirely superseded by Griffin. Here some confusion arises because a Welsh family of Griffin did actually settle in Ireland soon after the Anglo-Norman invasion. There is no doubt, however, that the great majority of Irish Griffins are really O'Griffys of Gaelic stock and not descendants of the Welsh settlers. They are very numerous and the name with an estimated population to-day of over eight thousand persons, stands seventy-fifth in the list of commonest Irish surnames. These are chiefly found in Munster - Counties Clare, Limerick, Kerry and Cork.
There was a minor sept of O'Griffy situated south of the Kenmare river, whose existence is recorded as late as the sixteenth century, their location being indicated by the place-name Ballygriffin: little is known of them and they appear to have been absorbed by their powerful neighbours the O'Sullivans. It is possible that some of the Kerry and Cork Griffins are descended from that sept; but Griffin is predominantly a Thomond name.
The head of the O'Greefa, or O'Grifee, sept (so it was first spelt in English) was chief under the O'Deas of a territory in the south-eastern part of the barony of Inchiquin, Co. Clare, their seat being the castle of Ballygriffy, in the parish of Dysart, near Ennis. Gerald Griffin (1803-1840), best known as the author of that great Irish novel The Collegians, was of this leading O'Griffy family. Also in the literary sphere the Gaelic poet Muiris O Griofa, or Maurice Griffin (d. c. 1778) may be mentioned (Mr. Basil O'Connell's genealogical researches have led him to believe that Maurice Griffin was of a Co. Monaghan family which migrated to Co. Kerry in the eighteenth century).
The name is occasionally anglicized Griffith, but most Griffiths in Ireland are of Welsh origin. That name has been made illustrious in Irish affairs by several outstanding men, particularly by Sir John Griffith (1784-1878), the geologist and civil engineer, and by Arthur Griffith (1872-1922), founder with Edward Martyn of Sinn Fein, and president of Dail Eireann.