The Second Bloodiest: The Hundred Days Offensive
The Hundred Days Offensive is the final significant military effort of World War I. Between the 8th of August and the 11th of November 1918, the Allies initiated a series of offensives against the Central Powers. This followed the Spring Offensive. With the end of the Spring Offensive, the Allies planned a number of counter-offensives, under the command of French general Ferdinand Foch. By this time, there were large numbers of American troops available, and British reinforcements for the Western Front had returned from campaigns in Palestine and Italy.
The Hundred Days Offensive began with the Battle of Amiens, eventually leading to a retreat by the Central Powers and the armistice that ended World War I. The Battle of Amiens, beginning on August 8, was a remarkable success. A huge number of troops, as well as some 500 tanks, took the Central Powers entirely by surprise. Attacking from the rear, the Allies created a 15-mile break in the German lines. By the 10th of August, the Germans began to retreat to the Hindenberg Line.
The Allies continued their counter-offensives, progressively pushing the Germans further and further back toward and behind the Hindenberg Line. The Hindenberg Line was a defensive border established by the Germans in the winter of 1916 and 1917. A series of offensives, sometimes called the Grand Offensive, directly attacked the Hindenberg Line. As the Allied armies continued to push German troops further and further back toward Germany, supply lines were significantly impaired, further weakening the Germans. The fighting continued until only moments before the armistice was signed on November 11, 1918.
There are no exact figures for casualties in the Hundred Days Offensive, but estimates suggest 700,000 Allied casualties, including injuries and fatalities. German casualties numbered at least 760,000; however, many scholars believe that number is quite low. In addition, as a loss became self-evident, large numbers of German soldiers deserted.