Superior German staff work at division, corps and army level throughout the war was a major contributor to their run of successes. At the beginning of 1918 having defeated the Russians Hindenburg and Ludendorff resolved to win in the west. Tactically, their staff work was brilliant. Using only weapons that had failed at Verdun, they devised a long, comprehensive list of measures to smash through enemy field fortifications, which were then taught to all ranks in the attacking units. The German Army had tactical success during the Spring Offensive, but the Allies held strategic points. They were sure that a series of successful breakthroughs would snap their enemy's resolve, ignoring the fact that each victory sapped German strength, while their foes were continually strengthened by Americans flooding into France. The Germans were overwhelmed during the Hundred Days Offensive, and eventually agreed to an Armistice of 11 November 1918 with the Allies.