As to the general distribution of forces to meet the German offensive, one-half of the British strength was devoted to protecting the Channel ports, and the rest was thinly dispersed over the remaining front. It must be remembered that additional front amounting to 28 miles had been taken over by the British in January, and that Sir Douglas Haig was now responsible for 125 miles. In view of this length of line and 217 the extreme importance of the Channel ports, the general disposition of troops would seem to have been wise.
The Germans claim to have effected a surprise in March 1918--a contention which is scarcely justified. In his interesting, lengthy, but somewhat vague account of the assembly of the great attacking force, Ludendorff says that ammunition dumps had been increased all along the British front, that movement of troops was carried out at night, but that German aviators sent up to report could see signs of concentration on the area chosen for attack which the blind English were _unable to perceive_! This is not accurate, but one must admit that the German concentration and preparation were superbly done.
We knew that a general movement of troops from east to west had been started in November, and that roads and railways were being improved, artillery increased, and ammunition accumulated all along the front from Flanders to the Oise, and by the end of February indications became apparent that the attack would be on the Third and Fifth Armies.
On the 19th March the Intelligence Department reported to Sir Douglas Haig that the enemy preparations on the Arras-St. Quentin front were complete and that the attack would probably be launched on the 20th or 21st.
Ludendorff assumes that “nor did the enemy discover anything by other means ... otherwise his defensive measures would have been more effective and his reserves would have arrived more quickly.” In this his claim of surprise might seem to be justified, although the charge can be met by a statement of the considerations which influenced Sir Douglas Haig through this anxious period; he could give up no ground 218 in the northern portion of the British area where the Channel ports were threatened, and he knew that the ground was exceptionally dry and that preparations for an attack had been almost completed from the direction of Menin; the same applied to the centre, behind which lay the collieries of northern France, and important tactical features covering his lateral communications; in the south, in the Somme area, ground could be given up to a certain extent without serious consequences.