cavalry, and troops of the other corps in the necessary proportions."[1] Each brigade was to consist of two or more regiments. "The troops of the other corps" were artillerymen and engineers, but there was no indication as to what proportion of a division they were to be. A division staff or that of a detached brigade was still minimal—artillery, engineer, and ordnance officers. The regulations changed the system for designating divisions and brigades from being numbered according to the rank of their commanders to being numbered according to their position on the line, although the names of the commanders were still to be used in reports. Finally, the regulations provided that only the War Department could authorize the formation of divisions and brigades during peacetime. In practice, such units would thus remain only wartime expedients.[2]
Civil War
The Civil War brought about the first large armies in the nation's history, and both Union and Confederate leaders used brigades, divisions, and army corps as command and control units. After rebel troops fired on Fort Sumter, South Carolina, President Abraham Lincoln called for 75,000 militiamen to assist the Regular Army in quelling the rebellion. Shortly thereafter Congress began to expand the Regular Army and call for volunteers. Following the rout of the Union forces at Manassas in July 1861 Congress authorized the first large call for men, 500,000 volunteers to serve three years. To train the new Army Lincoln selected George B. McClellan, a former West Point officer and president of the Eastern Division of the Ohio and Mississippi Railroad Company.[3] McClellan later described the Union troops at Manassas, who were mostly militia, as "a collection of undisciplined, ill-officered, and uninstructed men" instead of an army. The new commander in chief had much to do.[4]
As the volunteer regiments arrived in the Washington, D.C., area, McClellan began to organize them into what became known as the Army of the Potomac. During the course of the war additional Union armies were formed and served, but the experience of the Army of the Potomac serves as the model to illustrate the difficulties faced by commanders on both sides in organizing their forces. As many of the future leaders of the Army after the war fought with the Army of the Potomac, their experiences had a profound impact on Army organization in the last half of the nineteenth century.
In the Army of the Potomac the largest unit initially was a division, which consisted of three infantry brigades, one cavalry regiment, and four artillery batteries. The division commander did not have a staff, except for his three aides and an assistant adjutant general. The brigade commander, on the other hand, had two aides, a surgeon, a commissary of subsistence, an adjutant general, and a quartermaster.[5]
McClellan planned to organize the volunteers into brigades, divisions, and army corps. Each army corps, about 25,000 men, was to consist of two or more divisions. He hesitated to implement that organization, however, until his offi-
- ↑ Regulations of the Army of the United States, 1857, p. 13.
- ↑ Ibid,, pp. 13, 71–73.
- ↑ George B. McClellan, McClellan's Own Story: The War of the Union (New York: Charles L. Webster and Co., 1887), p. 2; War Department General Orders (WD GO) 49, 1861.
- ↑ McClellan, McClellan's Own Story, p. 68.
- ↑ The War of the Rebellion: A Compilation of the Official Records of the Union and Confederate Armies, Ser. 1, 53 vols. (Washington, D.C.; Government Printing Office, 1881–98), 5:11–17, hereafter cited as OR; WD GO 49, 1861.
