Meanwhile, officers of the French General Staff had journeyed to London to confer with the British General Staff regarding the camping and alignment of the British troops. Meanwhile, also, the British reserves and territorials were called to the colors. The latter comprised the militia, infantry and artillery, and the volunteer yeomanry cavalry, infantry and artillery. The militia was the oldest British military force, officered to a great extent by retired regular army men, its permanent staffs of noncommissioned officers were from the regular army, and it was under the direct control of the Secretary of State for War. The volunteer infantry, artillery, and yeomanry cavalry were on a somewhat different basis, more nearly resembling the American militia, but the British militia were linked with regular-line battalions. The reserves, militia and volunteers, added approximately 350,000 well-trained men for immediate home defense.
On Sunday, August 17, 1914, it was officially announced that the whole of the British Expeditionary Army had landed in France. Conferences between the British and French General Staffs resulted in the British army being concentrated first at Amiens. From that point it was to advance into position as the left wing of the united French and British armies, though controlled by their separate commanders.
The French Fifth Army had already moved to hold the line of the River Sambre, with its right in touch with Namur. Cavalry patrols had been thrown forward to Ligny and Gembloux, where they skirmished with uhlans. Charleroi was made French headquarters. It was the center of extensive coal-mining and steel industry. Pit shafts and blast furnaces dominated the landscape. Historically it was the ground over which Bluecher’s Fourth Army Corps marched to the support of the British at Waterloo. Now the British were supporting the French upon it against their former ally.
On Thursday, August 20, 1914, the British took up their position on the French left. Their line ran from Binche to Mons, then within the French frontier stretched westward to Conde. From Mons to Conde it followed the line of the canal, thus occupying an already constructed barrier. Formerly Conde was regarded as a fortress of formidable strength, but its position was not held to be of value in modern strategy. Its forts, therefore, had been dismantled of guns, and its works permitted to fall into disuse. But the fortress of Maubeuge lay immediately in rear of the British line. In rear again General Sordet held a French cavalry corps for flank actions. In front, across the Belgian frontier, General d’Amade lay with a French brigade at Tournai as an outpost.