As described in historical dictionaries

Patronymica Britannica (1860)

DEVENISH. The flimily first appear as gentry in co. Sussex about the year 1399. The name, clearly indicative of a Devonshire origin, is cognate with Kentish, Cornish, &c. The Irish branch, who transferred themselves to the sister island in tlie reign of Henry VIII., have a tradition

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


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