The years 1915–17 saw the Imperial German Army forced to adapt to the new realities of static trench warfare. Prewar uniforms and equipment had to be modified, for both utility and economy; on battlefields ruled by machine guns and artillery the steel helmet reappeared, as well as masks to protect against poison gas. Fashionable cavalry regiments soon proved irrelevant on the Western Front; many were dismounted to join the infantry, while new units usurped their prestige — assault battalions, and the air corps. This second volume in a three-part sequence offers vast detail on organisation, uniforms and insignia, illustrated with rare photographs and meticulous colour artwork.