The indecisive Second Battle of Ypres, from April 22 – May 25, was the site of the first German chlorine gas attack and the only major German offensive on the Western Front in 1915. Ypres was devastated after the battle. The Second Battle of Artois, from May 9 – June 18, the most important part of the Allied spring offensive of 1915, was successful for the Germans, allowing them to advance rather than retreat as the Allies had planned, and Artois would not be in Allied hands again until 1917. The Second Battle of Champagne, from September 25 – November 6, was a general failure, with the French only advancing about , and not capturing the German's second line. France suffered over 140,000 casualties, while the Germans suffered over 80,000.