Tanks in World War I

The development of tanks in World War I was a response to the stalemate that had developed on the Western Front. Although vehicles that incorporated the basic principles of the tank (armour, firepower, and all-terrain mobility) had been projected in the decade or so before the War, it was the heavy casualties sustained in the first few months of hostilities that stimulated development. Research took place in both Great Britain and France, with Germany only belatedly following the Allies' lead.

In Great Britain, an initial vehicle, nicknamed Little Willie, was constructed at William Foster & Co., during August and September 1915. The prototype of a new design that would become the Mark I tank was demonstrated to the British Army on February 2, 1916. Although initially termed "Landships" by the Landships Committee, production vehicles were named "tanks", to preserve secrecy. The term was chosen when it became known that the factory workers at William Foster referred to the first prototype as "the tank" because of its resemblance to a steel water tank.

The French fielded their first tanks in April 1917 and went on to produce far more tanks than all other combatants combined.

The Germans, on the other hand, began development only in response to the appearance of Allied tanks on the battlefield. Whilst the Allies manufactured several thousand tanks during the War, Germany deployed only 20 of her own.

The first tanks were mechanically unreliable. There were problems that caused considerable attrition rates during combat deployment and transit. The heavily shelled terrain was impassable to conventional vehicles, and only highly mobile tanks such as the Mark and FTs performed reasonably well. The Mark I's rhomboid shape, caterpillar tracks, and 26-foot (8 m) length meant that it could navigate obstacles, especially wide trenches, that wheeled vehicles could not. Along with the tank, the first self-propelled gun (the British Gun Carrier Mk I) and the first armoured personnel carrier (the British Mk IX) were also constructed in World War I.

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