Also Known As
- First Battle of Cold Harbor,
- Battle of Chickahominy River
Date and Location
- June 27, 1862
- Hanover County, Virginia
Principal Union Commanders
- Major General George B. McClellan
- Brigadier General Fitz John Porter
Principal Confederate Commanders
- General Robert E. Lee
Union Forces Engaged
- Army of the Potomac
Confederate Forces Engaged
- Army of Northern Virginia
Number of Union Soldiers Engaged
- Roughly 34,000
Number of Confederate Soldiers Engaged
- Roughly 57,000
Estimated Union Casualties
- 6,837 (894 killed, 3,107 wounded, 2,836 missing or captured)
Estimated Confederate Casualties
- 7,993 (1,483 killed, 6,402 wounded, 108 missing or captured)
- Confederate victory
- The Battle of Gaines’s Mill was the third engagement of the Seven Days Battles during the Peninsula Campaign.
- The Battle of Gaines’ Mill was Confederate General Robert E. Lee’s first major victory in the Civil War.
- The Battle of Gaines’ Mill was the largest of the Seven Days Battles.
- The last Confederate assault against Union lines at the Battle of Gaines’ Mill employed 32,000 Rebel soldiers and was the largest of the Civil War.
- The Battle of Gaines’ Mill was the only clear-cut Confederate tactical victory of the Peninsula Campaign.
- Seven Union soldiers were awarded the Medal of Honor for valor during the Battle of Gaines’ Mill.
Timeline of the Peninsula Campaign
These are the main battles and events of the Peninsula Campaign in order. The battles that occurred from June 25 to July 1, 1862, are collectively known as the Seven Days Battles.
- March 8–9, 1862 — Battle of Hampton Roads
- April 5–May 4, 1862 — Siege of Yorktown
- May 5, 1862 — Battle of Williamsburg
- May 15, 1862 — Battle of Drewry’s Bluff
- May 31–June 1, 1862 — Battle of Seven Pines
- June 25, 1862 — Battle of Oak Grove
- June 26, 1862 — Battle of Beaver Dam Creek
- June 27, 1862 — Battle of Gaines’ Mill
- June 29, 1862 — Battle of Savage’s Station
- June 30, 1862 — Battle of Glendale
- July 1, 1862 — Battle of Malvern Hill