Naval artillery is artillery mounted on a warship, originally used only for naval warfare, later also for naval gunfire support against targets on land, and for anti-aircraft use. The term generally refers to tube-launched projectile-firing weapons and excludes self-propelled projectiles like torpedoes and rockets, and those simply dropped overboard like depth charges and naval mines.
The idea of ship-borne artillery dates back to the classical era. Julius Caesar indicates the use of ship-borne catapults against Britons ashore in his Commentarii de Bello Gallico. The dromons of the Byzantine Empire carried catapults and fire-throwers.
From the late Middle Ages onwards, warships began to carry cannon of various calibres. The Battle of Arnemuiden, fought between England and France in 1338 at the start of the Hundred Years' War, was the first recorded European naval battle using artillery. The English ship Christopher was armed with three cannons and one hand gun.
By the 15th century most Mediterranean powers were utilising heavy cannon mounted on the bow or stern of a vessel and designed to bombard fortresses on shore. By mid-century some vessels also carried smaller broadside cannons for bombarding other vessels immediately prior to an attempted boarding. These small guns were anti-personnel weapons and were fired at point blank range to accompany engagement with muskets or bows.
From the 1470s both the Portuguese and Venetian navies were experimenting with cannons as anti-ship weapons. King John II of Portugal is credited for pioneering, while still a prince in 1474, the introduction of a reinforced deck on the old Henry-era caravel to allow the mounting of heavy guns for this purpose. These were initially wrought iron breech-loading weapons known as basilisks, but by the early fifteenth century the navies of the Mediterranean had universally adopted lighter and more accurate muzzleloaders, cast in bronze and capable of firing balls or stones weighing up to 60 lb (27 kg). In 1489 John of Portugal further contributed to the development of naval artillery by establishing the first standardized teams of trained naval gunners (bombardeiros).