[2] It was estimated in 2000 that Griffin is the 114th most common surname in the U.S., with a population in the order of two hundred thousand.

According to historian C. Thomas Cairney, the O'Griffeys were one of the chiefly families of the Dal gCais or Dalcassians who were a tribe of the Erainn who were the second wave of Celts to settle in Ireland between about 500 and 100 BC.

[3] The spelling Ó Gríofa (male) or Ní Ghríofa (female) is associated with the Co. Clare family, whose surname was also anglicised as O'Griffey or O'Griffy.

The Ó Gríofa were chieftains of the Cineal Cuallachta branch of the Dál gCais, or Dalcassians, with their castle at Ballygriffy located in North Ballygriffey, Dysert (formerly the barony of Inchiquin).

[4] The "Ó Grifín" (male) / "Ní Ghrifín" (female) spelling belongs to the Kerry family.