With the introduction of the tracked Mark I tank in 1916, the British sought additional applications of their invention with an eye toward breaking the stalemate of World War I trench warfare. One such variant was the Mark I gun carrier, history’s first tracked, self-propelled artillery.
Designed by an engineer at tank manufacturer Metropolitan Carriage, Wagon & Finance, the carrier was based on a lowered tank chassis with a bed to accommodate a British BL 5-inch field cannon or 6-inch howitzer, their respective wheels removed and mounted along the carrier’s hull. Transporting the artillery piece to the field, the carrier crew could remove it by means of a pivoting cradle and two winding drums and remount it on its wheels. In theory, the crew could fire either gun from the vehicle. In practice, only the howitzer was fireable while in motion.
The engineer completed a prototype in time for Tank Trials Day at Oldbury on March 3, 1917, and the army immediately placed an order for 50 gun carriages with Kitson & Co. in Leeds. In July the army formed two companies, each comprising two dozen gun carriers. They first saw action at Cambrai in November 1917. There is no record of a carrier crew ever firing its gun in combat, but they did provide useful frontline service as supply vehicles. Two were equipped with cranes for salvage work. Awkward as the Mark I was, it set the precedent for a range of self-propelled weaponry that would see widespread use among all combatants in World War II and thereafter.