Here are all of the Army Corps and Division-size units and their commanders who participated in the Maryland Campaign of 1862.
Federal units are listed by Corps and Division number, Confederates by Commanders' names. Each unit name is a link to more information about it and to the subsidiary units which made it up. Officers' names are links to brief biographical information and (sometimes) pictures of them.
Note that in some cases more than one officer is listed for a unit. This occurs when the original (first listed) commander was killed, wounded, relieved, or moved to another command and was replaced by the next named officer.
For a different view, in the form of an interactive tree diagram down to the battery and regiment levels, click on one of the tree diagram images below the names of the Generals Commanding.
THE ARMY OF THE POTOMAC
Major General George B. McClellan, USA, commanding
THE ARMY OF NORTHERN VIRGINIA
General Robert E. Lee, CSA, commanding
FIRST ARMY CORPS
(MGen. Joseph Hooker) (BGen. George G. Meade)
First Division - (BGen. John P. Hatch) (BGen. Abner Doubleday)
SECOND ARMY CORPS
(MGen. Edwin V. Sumner)
First Division - (MGen. Israel B. Richardson) (BGen. John C. Caldwell) (BGen. Winfield S. Hancock)
FIFTH ARMY CORPS
(MGen. Fitz John Porter)
x First Division - (MGen. George W. Morell)
SIXTH ARMY CORPS
(MGen. William B. Franklin)
First Division - (MGen. Henry W. Slocum)
NINTH ARMY CORPS
(MGen. Jesse L. Reno) (MGen. Ambrose E. Burnside) (BGen. Jacob D. Cox)
First Division - (BGen. Orlando B. Willcox)
TWELFTH ARMY CORPS
(MGen. Joseph K. F. Mansfield) (BGen. Alpheus S. Williams)
First Division - (BGen. Alpheus S. Williams) (BGen. Samuel W. Crawford) (BGen. George H. Gordon)
CAVALRY DIVISION (BGen. Alfred Pleasonton)
x - Unit not present and/or not engaged at Antietam on 17 September.
MIDDLE DEPARTMENT/8th ARMY CORPS
(MGen. John E. Wool)
Harpers Ferry Garrison - (Col. Dixon S. Miles) (BGen. Julius White)
LONGSTREET'S COMMAND (CORPS)
(MGen. James Longstreet)
McLaws' Division - (MGen. Lafayette McLaws)
JACKSON'S COMMAND (CORPS)
(MGen. Thomas J. "Stonewall" Jackson)
Ewell's Division - (BGen. Alexander R. Lawton) (BGen. Jubal A. Early)