Jenkins' Ear, War of, a naval war between Britain and Spain, 1739–43. The war originated with British attempts to smuggle goods into the Spanish American colonies. Robert Jenkins, captain of a British smuggling vessel, was seized by a Spanish coast guard ship and had one of his ears cut off. Parliament forced its leader, Sir Robert Walpole, to declare war against his wishes.

Contrary to expectations, the war proved neither easy nor profitable for Britain. Neither side gained any important victories. In 1743 the war became a part of a general European struggle, the War of the Austrian Succession (1740–48), in which Britain opposed France, Spain, and Prussia.