The Gas War 1915 – 18: If not a War-Winner, hardly a Failure

Edward M. Spiers
University of Leeds

As poison gas was a rare example of a weapon developed in one major war that was not used in the next, it has been depicted in some writings as a ‘failure’ in the First World War. My paper will argue that this view would have baffled contemporaries, who invested heavily in the research and development and the production of gas warfare, both offensively and defensively. The principal belligerents, I shall argue, were always seeking a competitive advantage whether in terms of the gas used, the methods of projection, the tactics that combined chemical and conventional munitions, and the increasing levels and refinements in the usage of chemical weapons. If gas did not break the stalemate of the trenches, neither did any other weapon, including the tank or the aircraft, but gas evolved into a ‘force multiplier’, compounding the effects of conventional weapons and degrading the effectiveness of enemy forces compelled to wear gas masks for protracted periods of time. The introduction of mustard gas, the ‘king of the war gases’, in July 1917 proved a watershed in the gas war, greatly increasing the number of British and later American casualties, and set the scene for a steady increase in the use of chemical weapons both offensively and defensively during the later stages of the war. Even if the investment in the gas war paled by comparison with that in the conventional war, the continuing innovation in the types of gases used, and in their methods of dissemination, underscored the continuing utility of the weapon and of the hopes attached to it.