21 Feb - 18 Dec, 1916 The Battle of Verdun is considered to be the greatest and the longest in world history. The Battle caused over an estimated 700,000 casualties. The battle happened on the Western Front between the Germans against the French armies. It was originally planned by the German Chief of General Staff, Erich von Falkenhayn to secure victory for Germany on the Western Front. The aim was to crush the French army before the Allies grew in strength with the help of the British forces.