During the warm mid summer of 1914 few people suspected that, by August, Europe would be plunged into the bloodiest conflict known to mankind. Patriotic fervour - often misplaced -swept through the participating countries, but the troops dispatched to the battle fronts soon realised that the popular view: "it will all be over by Christmas", was just an optimistic dream. In the face of the relentless German advance into Belgium, the British Expeditionary Force was engaged in the costly retreat from Mons. The German Army soon took Antwerp, and only the "miracle of the Marne" stopped them from marching into Paris. The First Battle of Ypres prevented the Germans from reaching the coast, but both sides dug in and the wretched system of trench warfare was established. Following the extraordinary Christmas truce, ferocious fighting restarted over the snow covered battlefields, and casualties on both sides were heavy. In the late spring of 1915 the second Battle of Ypres took place and the Germans used poison gas for the first time. The toll in killed and wounded was disastrous, the British alone losing 50,000 men; but the Allies finally, managed to halt the enemy advance.