“Jenkins's Ear,” refers to an incident which provoked a war with Spain in 1739, viz., the conduct of the officer of a Spanish guardship not far from Havana towards the captain of an English trading ship of the name of Jenkins; the Spaniards boarded his ship, could find nothing contraband on board, but treated him cruelly, cut off his left ear, which he brought home in wadding, to the inflaming of the English people against Spain, with the above-named issue.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Jena * Jenner, Edward