Artillery Impacts on Siege Warfare

This effect was exaggerated by a general shortage of cannon that was not made up until discovery of new iron casting techniques in England, which made cheap cannon available even for emplacement in fortified defenses. This shifted the firepower imbalance back to the defense. Revived usefulness of fortifications in turn resuscitated siege warfare. By the time of the Italian Wars (1494-1559), cannon played a major role in deciding the outcome of sieges, though they were still problematic in battle because they remained largely immobile once position was taken and the first shot fired.

Dragging cannon close to enemy parapets exposed guns and crew to capture or death should the defenders sortie, or a skilled archer land a flame-arrow among the powder sacks. That meant a besieging army had to deploy more troops to defend the guns, a tactic met by more men in the sortie, and so on. Early siege cannon were also slow-firing and defended by easy counter-measures such as hanging fascines of wood and wool wadding over outer walls. Even so, some did enough damage to stone defenses that were otherwise unbreachable to make worthwhile hauling big guns by barge or overland (using as many as 40 oxen per gun), handling the treacherous black powder that was their constant companion, paying master gunners to conduct the bombardment, and devoting hundreds of expensive mercenaries to protect the guns.

All that was justified by the resulting broken walls, dead enemies, ceded positions, and war booty. Improved casting technology allowed guns to move back, out of range of archers or mounted sorties. By the early 15th century bombards could hurl stone balls 25 inches in diameter great distances, causing severe damage to fortifications unprotected by shock-absorbing earthworks. Experimentation led to gigantism, and huge bombards were assembled that were so impressive they were given names. With such great bombards as ”Elipolos” (”City-Taker”) Muhammad II smashed the high walls of Constantinople that had withstood a dozen prior sieges over a thousand years.

That same year, the French used cannon to crush an English army at Castillon, the final battle of the Hundred Years’ War. By then cast-iron cannonballs were in wider use, better recipes for gunpowder were crafted, and gunners were more skilled. Other innovations included primitive explosive shells, improved wheeled gun carriages from 1470, and rifling of some guns as early as 1520. Accuracy, throw weight, range, and power had all increased. The Age of Castles was over and the Age of Artillery began. Whatever chivalry and glory there ever was in medieval warfare was burned away by the new, and utterly morally indifferent, weapons of the gunpowder age.