Bringing in French prisoners in a suburb of Verdun, France, 1916. Verdun was the site of a major battle of the First World War. One of the costliest battles of the war, Verdun exemplified the policy of a "war of attrition" pursued by both sides, which led to an enormous loss of life. The battle lasted 11 months. At a cost of some 400,000 German casualties and a similar number of French, the attack was finally called off. Germany had failed to bleed France to death.