We may anticipate here by saying that on October 19 the detrainment of the 1st British Army Corps, under the command of General Sir Douglas Haig was completed at St. Omer; that on the same date the 10th French Army, under the command of General Maudhuy, reached the line between Ypres and Dixmude; and that on October 20 the first of the Indian troops, the Lahore Division, also arrived at the front.
There were now three armies, the Belgians, the French, and the British, the latter consisting, with the Indians, of four Corps. The 10th French army included a division of Marines from Brest, and a Corps of Moroccans and Senegalese. This was the force, equivalent, with the two bodies of British and French cavalry, to some 320,000 men, on which fell during the ensuing four weeks, the weight of an attack by eighteen German army corps mustering in the aggregate nearly 1,080,000 of all arms.
These German forces included:
The troops of General von Deimling liberated by the evacuation of Antwerp, among them a division of Marines;
The army of the Duke of Wurtemberg, comprising the 22nd, the 23rd, part of the 24th, the 26th, and the 27th Reserve (Landwehr) Corps;
The army of General von Fabeck, consisting of four Corps and one division;
The army of the Crown Prince of Bavaria, comprising the Prussian Guards, the 4th, 7th, 13th, 14th and 19th Corps; the 18th Reserve Corps; and the 1st Bavarian Reserve Corps.[7]
The gathering together of this vast mass of combatants does not appear to have been completed until October 23 or 24. Such delay as occurred, though in fact the massing was carried out at remarkable speed, sprang not from the embodiment of fresh formations, nor from any difficulty in sending them westward from Germany. In order to make up this force which was intended to be another spear head, the Germans had creamed the whole of their fighting front in the West. Having before them the example of the transfer of the British army from the Aisne, they had taken a leaf out of the book of the Allies. All save the best of their Reserve Corps had been distributed along their front. These new levies released the more reliable and seasoned men alike of the Active army and of the Landwehr, and the importance of the Battle of Ypres is, apart from other consequences, that it broke or destroyed the best of the remaining troops of Germany.
To begin with, the weight of the German counter-offensive was thrown, not against Ypres, but against the British positions to the west of Lille. Their objective was to secure La Bassee, the little mining town on the northern edge of the coalfield, some eight miles to the south-west of Lille. This point it is now clear they intended to make the immediate pivot on which to swing round their northern front. As the British positions at this time stood, communication between Lille and La Bassee by the main road was cut. There is another point it is insistent to notice. La Bassee lies at the end of one of the promontories of the inland "coastline." It was already held by the Germans and the spur had been strongly entrenched.
Yet another reason dictated the plan. One of the evident objects of the British operations was to push down the Lys and seize the crossing and railway junction at Menin. That would not only have gravely embarrassed the German occupation of Lille, but would equally have embarrassed a development of their attack between the Lys and the coast.