Cedar Mountain to Antietam: A Civil War Campaign History of the Union XII Corps, July–September 1862

by M. Chris Bryan

This history of the Union XII Corps “skillfully weaves firsthand accounts into a compelling story about the triumphs and defeats of this venerable unit” (Bradley M. Gottfried, author of The Maps of Antietam).
 
The diminutive Union XII Corps found significant success on the field at Antietam. Its soldiers swept through the East Woods and the Miller Cornfield—permanently clearing both of Confederates—repelled multiple Southern assaults against the Dunker Church plateau, and eventually secured a foothold in the West Woods. This important piece of high ground had been the Union objective all morning, and its occupation threatened the center and rear of Gen. Robert E. Lee’s embattled Army of Northern Virginia. Yet federal leadership largely ignored this signal achievement and the opportunity it presented.
 
The achievement of the XII Corps is especially notable given its string of disappointments and hardships in the months leading up to Antietam. M. Chris Bryan’s Cedar Mountain to Antietam begins with the formation of this often-luckless command as the II Corps in Maj. Gen. John Pope’s Army of Virginia on June 26, 1862. Bryan explains in meticulous detail how the corps endured a bloody and demoralizing loss after coming within a whisker of defeating Maj. Gen. “Stonewall” Jackson at Cedar Mountain on August 9; suffered through the hardships of Pope’s campaign before and after the Battle of Second Manassas; and triumphed after entering Maryland and joining the reorganized Army of the Potomac.
 
The men of this small corps earned a solid reputation in the Army of the Potomac at Antietam that would only grow during the battles of 1863. This unique study, which blends unit history with sound leadership and character assessments, puts the XII Corps’ actions in proper context by providing significant and substantive treatment to its Confederate opponents. Bryan’s extensive archival research, newspapers, and other important resources, together with detailed maps and images, offers a compelling story of a little-studied yet consequential command that fills a longstanding historiographical gap.

Genres: Civil War, American Civil War

394 pages, Kindle Edition

Published January 4, 2022

Reviews

[Bill Harper · Rating 5 out of 5]

Excellent book about a forgotten Corps that fought for the Union. It covers a period of time that is many times overlooked in the history of the Civil War. The time between the Seven Days Battles and Antietam is many time glossed over with less than a chapter covering this time period. Which is a shame considering that the battles of Cedar Mountain, Second Manassas, Ox Run or Chantilly and the movement back to Washington. Where the Army of the Potomac was reorganized by combining it with the Army of Virginia. I recommend it for those who have an interest in the whole Antietam Campaign.

[Francis X DuFour · Rating 5 out of 5]

Very good accounts of two major battles

Bryan’s telling of the experiences of the Army of the Potomac’s hard-luck XII Corps well explains the trials of this organization. Roughly handled at Cedar Mountain, the corps entered the Battle of Antietam seriously depleted. The loss and incompetence of its field officers are vividly detailed in its confused and bloody fight in the Cornfield and around the Dunker Church.

[W. Charles Young · Rating 5 out of 5]

Bryan does a very good job of developing the history of the Federal 12th Corps from its antecedents through the Battle of Antietam. He does not veer from that focus throughout the book. He adroitly moves between the leadership of the corps and the common soldiers fighting in the ranks. It is a history worth reading and we can hope Bryan is working to continue the story beyond Antietam.