Field Artillery Before the 18th Century

Maurits also limited types and designs of gun carriages. Finally, he deployed a siege train of truly massive cannon. This was only possible because he also made innovative use of river transport, which could be done in the Netherlands but not everywhere. The largest guns in his train, known as ”Karouwen,” weighed up to 51⁄2 tons and had to be disassembled prior to transport by river or canal barge. This meant that their usefulness was limited to deployment against those garrisons and strongpoints reachable by barge, even in watery Flanders. On land, these behemoths needed 30 horses apiece to haul them into firing position. Dozens more horses pulled the heavy carts needed to bring their massive shot and tons of black powder used to hurl stone and iron death and destruction against enemy fortifications. All that took time. And slowing the pace of moving armies not only decreased the chance of achieving tactical surprise while permitting improvements to be made to the defense faced upon arrival, it hugely increased the logistics problem of feeding men and beasts of burden. Once the logistical wall was reached, campaigns quickly failed.

Even small field cannon (”demi” or ”half-cannon”) needed as many as 16 horses per gun to move. While wheeled gun carriages were pulled along main roads, albeit at an appallingly high rate of loss of horses or oxen to death-in-harness from overwork against the pull of mud and the raw strain of too much tonnage, they were not true field pieces since off-road maneuver was still extremely difficult. In battle, once positioned the guns stayed in place, allowing the enemy to evade their fire by moving or capturing them with a surprise attack. The innovations of Gustavus Adolphus took Maurits’ reforms and advanced them to deploy the first true field artillery. The great Swede accepted standardization and limited calibers, adding manufacture of interchangeable parts. Most important, he cast ultra-light, genuinely mobile guns which a single horse or two men might move. Gustavus’ famous early experiment with ”leather guns” failed, but he oversaw production of light iron cannon that were easily towed off-road and could be repositioned during battle. He cast bores as small as 11⁄2-pounders, and far more of his favorite 3-pounders. These he deployed in front of his infantry, and like his flexible infantry formations his field guns could adjust and move position as the battle unfolded. Some of his field pieces also achieved a rate of fire exceeding the rate of contemporary muskets. Finally, Gustavus reorganized his heaviest guns into batteries, to concentrate fire. That was a highly effective and still novel deployment. As Swedish-style guns were replicated and deployed by other armies, by the middle of the 17th century true field artillery arrived on the battlefield and changed the face of land combat.