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| Guards & Orderlies | Captain James B. McIntyre | |
| McClellan Dragoons (Illinois) | ||
| Sturgis (Illinois) Rifles | ||
| Oneida (New York) Cavalry Company | Captain Daniel P. Mann | |
| 1st United States Cavalry, Cos. BCH&I | Captain Marcus A. Reno | |
| 4th United States Cavalry, Cos. A & E | Captain James B. McIntyre | |
| Provost Guard | Major William H. Wood | |
| 93rd New York Infantry, Cos. AFH&K | Lt. Colonel Benjamin C. Butler | |
| 8th United States Infantry, Cos. ABDF&G | Captain Royal T. Frank | |
| 19th United States Infantry Cos. G&H | Captain Edmund L. Smith (Co. G) Captain Henry S. Welton (Co. H) |
|
| 2nd United States Cavalry Regiment | Captain George Gordon | |
| Engineer Brigade | Brigadier General Daniel Woodbury | |
| 15th New York Engineer Regiment | Colonel John M. Murphy | |
| 50th New York Engineer Regiment | Lieutenant Colonel William H. Pettes | |
| Regular Engineer Battalion | Captain James C. Duane | |
| Headquarters Staff | ||
| Chief of Staff | Brigadier General Randolph B. Marcy | |
| Chief of Artillery | Brigadier General Henry J. Hunt | |
| Chief of Cavalry | Brigadier General John Buford | |
| Chief Engineer | Captain James C. Duane | |
| Inspector General | Colonel Delos B. Sacket | |
| Assistant Adjutant General | Lieutenant Colonel Albert V. Coburn | |
| Chief Quartermaster | Lieutenant Colonel Rufus Ingalls | |
| Topographer | Captain Charles R. Lowell | |
| Medical Director | Surgeon Jonathan Letterman | |
| Chief of Signals | Major Albert J. Meyer | |