Chapter 8: Corps organizations.With the record of each regiment given in these pages will be found the division and corps to which it belonged. The history of a regiment is so largely identical with that of its corps, that such information serves at once to familiarize the student with the part which it played in connection with the war. An excessive loss in action, or an immunity from the casualties of battle, requires but little explanation where there is a thorough acquaintance with the history of the division and corps with which the regiment in question was connected. An additional interest, also, attaches to the record of each command as the history of its corps is fully understood. The corps badges, which were worn by many commands, were first ordered in the spring of 1863, and were adopted immediately by the Army of the Potomac; but in the Western armies these badges did not appear on the men's caps until 1864, and then they were only partially adopted. In some corps they were not worn at all. The badges were of various shapes and were stamped out of flannel cloth; in size, they were about an inch and one-half across, and were fastened conspicuously on the men's caps. They were of different colors, the first division of each corps wearing red badges; the second, white; and the third, blue. The idea originated in 1862 in Kearny's Division, in which the soldiers wore a diamond-shaped shaped piece of flannel on their caps. The corps badges which were most conspicuous during the war, by reason of their general use, were: the round or disc-shaped badge of the First Corps; the trefoil, or ace of clubs, worn by the Second; the lozenge, or diamond-shaped badge of the Third; the triangular patch of the Fourth; the Maltese cross, of the Fifth; the Greek cross, of the Sixth; the crescent of the Eleventh; the star, of the Twelfth; and the acorn, of the Fourteenth. The various corps were organized, for the most part, with three divisions, each division containing three brigades, and each brigade consisting of five regiments,--making 45 regiments of infantry in a corps, to which were added about nine batteries of light artillery. But this form was adhered to only as a general rule, and was varied at times to meet temporary exigencies. The greatest variation occurred in the brigades, the depletion, at times, of some regiments making additional ones necessary to keep up a proper effective strength. During the Atlanta campaign, some brigades in the Fourth and Fourteenth Corps contained nine regiments. Then, again, a corps would have occasionally four divisions, and some divisions would have four brigades; but such cases were exceptional, and generally proved to be but temporary arrangements. In 1863 the cavalry were organized into a corps by themselves; prior to that each corps was accompanied by a brigade of cavalry regiments. Batteries of light artillery, organized in brigades of about five batteries each, were attached to each corps, in addition to which the Army of the Potomac had an artillery reserve  consisting of five brigades--21 batteries in all. This Artillery Corps of the Army of the Potomac was under command of General Henry J. Hunt. Prior to the adoption of corps organizations, the various armies of the Union consisted of divisions numbered in the order of their formation. This plan was adhered to in the Western armies until December, 1862. The Army of the Ohio contained several divisions, each division containing three brigades. But these brigades were numbered without reference to their divisions, and hence, in the roster of the Army of Ohio, at Shiloh, we find, for instance, that the Fourth Division--Nelson's — was composed of the 10th, 19th and 22nd Brigades; and at Perryville, in the Eleventh Division--Sheridan's — the brigades were not the 1st, 2d, and 3d, but the 35th, 36th and 37th Brigades. The Army of the Tennessee contained six divisions at Shiloh, and the Army of the Mississippi fought at Iuka without any corps formation. This lack of proper organization did not last long, and in 1863 the Western armies took the field with corps organizations similar to those which General McClellan had instituted in the Army of the Potomac, and which were retained during the remainder of the war.
- Cedar Mountain -- Rappahannock -- Gainesville -- Groveton -- Second Bull Run -- South Mountain -- Antietam -- Fredericksburg -- Fitzhugh's Crossing -- Chancellorsville -- Gettysburg -- Mine Run.
The First Corps, when at its maximum, contained 46 regiments of infantry and 12 batteries of light artillery. It was organized in March, 1862, with three divisions,--King's, McCall's, and Franklin's. General Irwin McDowell was placed in command. When General McClellan moved the Army to the Peninsula, in April, 1862, McDowell's corps was left in Northern Virginia. Franklin's Division was ordered, soon after, to the Peninsula, where it was used in forming the Sixth Corps, its place in McDowell's command being taken by Ricketts' Division. In June, McCall's Division — the famous Pennsylvania Reserves--was also sent to the Peninsular Army, but upon the return of McClellan's forces to Washington, the Reserves rejoined McDowell, and fought under him at Second Bull Run. During the absence of the Army of the Potomac, McDowell was engaged in an active campaign which culminated in the battles around Manassas, the first general engagement in which the corps participated; loss, 595 killed, 2,853 wounded, and 2,021 missing, out of about 18,500 effective men. During the short time in which the army was under Pope, McDowell's Corps was officially designated as the Third Corps, Army of Virginia; but upon General McClellan's restoration to command it resumed its former and proper title,--the First Army Corps. While on the Maryland campaign the Corps was commanded by General Hooker, and the divisions by Generals Hatch, Ricketts and Meade; it numbered 14,850 men. It was prominently engaged at South Mountain, and also at Antietam, where it opened the battle, its casualties in that engagement amounting to 417 killed, 2,051 wounded and 122 missing. General John F. Reynolds was in command at Fredericksburg, with Doubleday, Gibbon and Meade as division generals; loss, 347 killed, 2,429 wounded, and 561 missing; total, 3,337. After this battle, the division of Pennsylvania Reserves--Meade's (3d) Division — was withdrawn from the front, and ordered to Washington that it might rest and recruit. This division, in addition to the battles of the First Corps, had served previously on the Peninsula, where it had encountered hard fighting and heavy losses. While on the Peninsula, the Reserves were attached to the Fifth Corps. When the division rejoined McDowell's Corps, at Manassas, it was with depleted ranks which were still further thinned by its subsequent battles. After taking its departure for Washington it never rejoined the First Corps, its  place being taken by a division composed of new troops,--Doubleday's (3d) Division. The corps was only slightly engaged at Chancellorsville, it being held in reserve. At Gettysburg, in the battle of the first day, this corps did some of the best fighting of the war. The division commanders on that field were Wadsworth, Robinson and Doubleday; General Reynolds, who was still in command of the corps, was killed just as he rode on the field, and before his troops were fairly engaged. General Doubleday succeeded to the command, and handled the corps during, that action in a remarkably able. manner. A noteworthy feature of that day was that the corps, although finally driven from the field by a superior force, succeeded in capturing, at different times and at different points on the field, parts of three brigades of the enemy,--Archer's, Davis', and Iverson's1--taking them in open field fighting, where there were none of the usual accessories of breastworks, intrenchments, or protection of any kind other than that which the field afforded. The First Corps fought that day with no other protection than the flannel blouses that covered their stout hearts. It contained 34 regiments of infantry, and 5 batteries of light artillery, numbering 9,403 infantry “present for duty, equipped;” loss, 593 killed, 3,209 wounded and 2,222 missing; total 6,024, out of less than 9,000 in action. Of the missing, a large proportion were killed or wounded. Prior to this battle, the roster of the corps had undergone considerable change. Eight New York regiments had gone home, their two years term of service having expired; also, one nine months regiment from Pennsylvania. These changes reduced the First and Second Divisions to two brigades each. The Pennsylvania Reserves had been replaced by a new division of two brigades, to which Stannard's Vermont Brigade was added just before the battle.