Some writers deduce this family from a noble Florentine who came to Scotland in the reign of Kenneth II. It is said, in the reign of Malcolm II., a Scotchman of high distinction having killed with his own hand Enrique, one of the Danish generals, at the battle of Murthill, cut off his head, and with the bloody dagger in his hand showed it to the king, and in the Gaelic language said Eriskyne, "upon the knife," alluding to the head and dagger; and in the same language also said, "I intend to perform greater actions than what I have done." Whereupon, King Malcolm imposed upon him the surname of Eriskine, and assigned him for his armor-bearings a hand holding a dagger, with "Je pense plus" for a motto, which has continued to be the crest and motto of this family.

Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.

ERSKINE. The name of this ancient and noble Scottish family is derived from the barony of Erskine on the Clyde, in Pienfrewshire, and it was first assumed by Henry of Erskine, about the year 1220.

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