The size of the armies, and the area covered by them, made it impossible for the Commander to exercise personal control over his whole force, especially as the absence of a system of supply entailed wide dispersion for subsistence on the country invaded. It became necessary to appoint independent Generals to command the scattered fractions of the Army, often operating at a distance from each other. This arrangement was instituted by Carnot in the early wars of the Revolution.
It thus came about that the Army was divided into separate portions, which were naturally termed its Divisions, a designation which was retained when they became permanent organizations, and exists in all armies to this day.
These Divisions consisted mainly of Infantry, but some Light Cavalry and Artillery were attached to them, so as to make them capable of the independent action demanded by the increased extent of the theatre of war and of the battlefields.
The Division comprised generally 12 Battalions of Infantry, 4 to 8 Squadrons, and 8 to 12 guns, with the necessary administrative services, making a total of some 10,000 to 12,000 in all, under command of a General Officer.
The Infantry was formed in what were termed Demi-Brigades of 3 Battalions, which reverted to the name of Regiments in 1803. These comprised one Battalion of regulars from the old Royal Army, and two of Volunteers. Each Battalion had 9 Companies, each about 120 strong; one being of Grenadiers, and two of Light Infantry. The Battalions were numbered, their old army name being dropped. The Cavalry Regiments were of 4 Squadrons, each 150 to 200 strong. The practice of living on the country allowed the transport train to be greatly reduced, especially as tents were discarded, and the troops always bivouacked, when not billeted. Company officers were allowed no bât animals for their baggage. By these measures the mobility of the army was greatly increased.
This divisional organization was adopted by Austria in 1805, by Prussia in 1806, and by Russia in 1807; we find it in the British Army in the Peninsula in 1808, when the Divisions were formed of 2 Brigades of 3 or 4 Battalions each, with 1 or 2 Batteries, and often a Rifle Battalion.
CORPS D’ARMÉE (ARMY CORPS)
The power of independent action thus conferred on these Divisions, which were in fact miniature armies, led to a want of concert in their movements, and of co-ordination in their action, while at the same time, as Armies increased in size, the number of Divisions became too great for the Commander-in-Chief to control properly.
An attempt to remedy these drawbacks was made in 1800 by Moreau, when planning his invasion of South Germany. He grouped his Divisions into two Wings and a Centre, which he placed under three senior Generals, while retaining a Reserve of four Divisions in his own hand. Each Division was either 5,000 or 10,000 strong, and 3 or 4 of them, with 6 guns per 5,000 men, and a Cavalry Division of 2,000 or 3,000, formed virtually a Corps d’Armée, 20,000 to 30,000 strong.
Bonaparte, when First Consul, grasping the desirability of this arrangement for large armies, introduced a permanent organization by Corps d’Armée.