In 1916, the Battle of Verdun between the French and Germans may have been the most demanding battle in world history. The struggle started when the Germans attacked Verdun, France, a city surrounded by a ring of underground forts. At least 220,000 soldiers died, and at least 480,000 were wounded in this 10-month struggle that accomplished next to nothing. At the end the front lines were in nearly the same locations as at the beginning.

Verdun was milestone in military strategic thinking in that the intention from the outset was attrition, not victory. German war planners calculated that for each German loss, France would lose two soldiers to defend a vital strategic fortress. In the end, the losses were more like 1:1. Verdun became known among soldiers as "the meat grinder."