When, after the German defeat on the Marne in September, 1914, and the check to the Allies on the Aisne, the race to the northern sea began with the Germans keeping a step in advance and thus blocking the constant French attempt to outflank them from the west, all the high ground in this region was occupied by the Germans; and when the fronts became rigid the French found themselves in a dangerously insecure position with the German possession of the high hill of Notre Dame de Lorette threatening all the coal fields of northern France and the southern shore of the Channel. During the winter of 1914-15 the French organized their attack, and in the early summer they set themselves doggedly to the task of turning the Germans out of these strong places. The enemy held the towering hill of Notre Dame and the cluster of houses known as Ablain St. Nazaire at its foot; across the little Souchez river the village of Carency on a slight eminence; a mile or so to the south the hamlet of Neuville St. Vaast, on the crest of a swell in the ground; southward from the latter point and stretching eastward almost to the base of Vimy Ridge they had prepared a huge network and maze of trenches and redoubts which acquired a sinister renown under the name of the Labyrinth. For weeks during the summer of 1915 the battle raged here continuously; and literally the French drove the Germans foot by foot and yard by yard from these positions; out of Carency and down the Souchez valley; back step by step from the heights of Notre Dame; trench by trench the Labyrinth was wrested from them; and by the late summer the Germans had withdrawn behind the great ridge of Vimy which lay athwart the path of the advancing French. There they stood savagely at bay, and when the French, in unison with the British attack at Loos, north of Lens, essayed in October to storm the hill, they exacted a bloody revenge for their earlier defeats. Afterwards this area became part of the British front, when the French moved to the south bank of the Somme; and after a year of inactivity, varied by a single unsuccessful attack upon a portion of the ridge’s defences by a British brigade, the Canadians, in the winter of 1916-17, took over this sector and set themselves the task of taking the Ridge as their initial contribution to the great spring offensive that was foreshadowed.