Description Lys, 9 - 27 April 1918. Ludendorff still hoped to destroy the hard-hit British Army before it had a chance to recover from the effects of the Somme drive. This was the purpose of a new German attack launched on 9 April 1918 on a narrow front along the Lys River in Flanders. The Germans committed 46 divisions to the assault, and, using Hutier attacks once again, quickly scored a breakthrough. The British situation was desperate for some days. Haig issued his famous "backs to the wall" order and appealed to Foch for reinforcements. But the Allied Supreme Commander, convinced that the British could hold their line, refused to commit reserves he was building up in anticipation of the day when the Allies would again be able to seize the initiative. Foch's judgment proved to be correct, and Ludendorff called off the offensive on 29 April.
Since 21 March the Germans had suffered some 350,000 casualties without having attained any vital objectives; in the same period British casualties numbered about 305,000. About 500 Americans participated in the campaign, including troops of the 16th Engineers, 28th Aero Squadron, and 1st Gas Regiment.