German gains in early 1918

The Second Battle of the Marne (French: Seconde Bataille de la Marne), or Battle of Reims (15 July – 6 August 1918) was the last major German Spring Offensive on the Western Front during the First World War. The German attack failed when an Allied counterattack led by French forces and including several hundred tanks overwhelmed the Germans on their right flank, inflicting severe casualties. The German defeat marked the start of the relentless Allied advance which culminated in the Armistice about 100 days later. Thus the Second Battle of the Marne can be considered as the beginning of the end of the Great War.

• http://en.wikipedia.org/wiki/Second Battle of the Marne