As described in historical dictionaries

Patronymica Britannica (1860)

FINN. A native of Finland. A-Sax. plur. Finnas. Fin. H.R.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.


Origin: Celtic

Region of origin: British Isles

Country of origin: Ireland

Religion of origin: Christian

Language of origin: Gaelic

BritishSurnames.uk is a Good Stuff website.