Battle of Gaines' Mill

Location: Hanover County, VA
           (near Mechanicsville, VA)
Dates: June 27, 1862
Union Commander:  
Fitz John Porter,
                                        Brigadier General
Confederate Commander: 
Robert E. Lee, General

Battle Summary:
After pushing to the "Gates of Richmond," George B. McClellan's Army of the Potomac was positioned to bring siege to the Confederate capitol.  However, with CS General Joseph Johnston's severe wounding, at Seven Pines, the soon to be christened Army of Northern Virginia, had a new commander - CS General Robert E. Lee.  Lee would immediately go on the offensive, pushing McClellan's army southeast, at the battle of Mechanicsville.  McClellan, noting the arrival of CS Major General Thomas Jackson's divisions, came quickly to the conclusion that he was facing a vastly larger army, then he actually was.  While Jackson did not attack McClellan's army, his presence off McClellan's right flank threatened his railroad supply line.  McClellan's next fateful decision would set the tone for the remainder of what was known as The Seven Days campaign.  He decided that he would make the James River his supply base and quickly put his army in motion.  The supply base on the James would not have a railroad link to the Army of the Potomac, so his grand plan to siege Richmond came to an end.

As George McClellan began putting his Corps in motion, he ordered Fitz John Porter to move behind the Boatswain's Swamp, five miles from his current position at Beaver Dam Creek.  Porter would deploy his V Corps on a plateau on the southeast side of the swamp, while the other four Federal corps would retreat across the Chickahominy River on their way to their new camp, on the James.  Unfortunately with the Chickahominy rising, Porter's V Corps (at 30,000 it was the largest in McClellan's army), was trapped at Boatswain's Swamp.  At his best here, Porter set up a line, almost two miles long, along a plateau, with trenches also below the plateau, near the swamp.  Commanding his divisions were US Brigadier General George W. Morrell, US Brigadier General George Sykes and US Brigadier General George McCall.  Porter placed Morrell's division, on his left, with its left flank near the Chickahominy River.  Sykes's division would represent the army's right flank, protecting the Grapevine bridge.  McCall's division would be in the center.  Additionally, Porter positioned his artillery to concentrate on any openings in the woods above the swamp.

Meanwhile, Robert E. Lee ran into many difficulties pursuing McClellan's army towards the Chickahominy River.  Most of his difficulties were traced to faulty maps, and in Thomas Jackson's case, to a wrong turn recommended by a local guide.  However, by the morning of June 27, A.P. Hill's Light Division had arrived at New Cold Harbor.  Lee immediately put his division in motion, across a 1/4 mile of open fields - towards Boatswain's Swamp.  In the lead, would be CS Brigadier General Maxcy Gregg's brigade.  With the Federal cannon raining case, and shell on them, Gregg's veterans raced across the field, down through Boatswain's Swamp and to the top of the crest, where they took a short rest.  Gregg's subsequent attack, would come against the center of the Federal line held by US Colonel Gouverneur K. Warren's brigade, of George Syke's division.  This brigade included the fighting Zouaves of the 5th New York.  As Maxcy Gregg's South Carolinians charged across the open field, towards Warren's position, the Yankee troops charged into them.  This opening phase of the battle would include much hand-to-hand combat, with clubbed muskets, fists and bayonets being the primary weapons.  After nearly half the combatants were killed, or wounded, the Confederates withdrew to the trees of Boatswain's Swamp.

This type of piecemeal attack was typical of the opening salvos of the battle at Gaines' Mill.  On the Confederate left, CS Major General Daniel Harvey Hill would send the 20th North Carolina, of CS Brigadier General Samuel Garland, Jr.'s brigade, against the far right of George Syke's line.  They would have some success, and would capture several cannon, however, the victory would be short lived, as a Federal counterattack would recapture the guns after a short time.

On the Confederate right, the division of CS Major General James Longstreet was held in reserve, awaiting the arrival of Thomas Jackson's division.

Around 5:00 PM, with the arrival of Jackson's men, Robert Lee set to organizing his troops for an all out assault against Fitz John Porter's V Corps.  Realizing the danger, Porter faced, McClellan dispatched reinforcements commanded by brigadier generals Henry Slocum, William French and Thomas Meagher. With these additional 15,000 troops, there were nearly 100,000 combatants arrayed at Gaines' Mill.

Lee's all out assault would start at 7:00 PM, and would focus on George Morrell's Federal division - over ground that A.P. Hill's division struggled earlier.  Leading this division would be the brigades of  CS Brigadier General John Bell Hood and CS Colonel Evander Law.  Asked by Lee, prior to the charge, if he could break their line, Hood said, "I will try."  Marching to the left of Law's brigade, Hood's attack would land in a weakened spot in the Federal lines.  Told not to fire until they reached the enemy lines, the assault was too much for the Federals and Hood's attack would pierce the line.  Broken regiments of Morrell's division began to retreat, which ended up causing a general retreat along the entire Union line.  With light rapidly fading, Fitz John Porter started a withdrawal towards the Chickahominy River, under cover of darkness.

One last action, would stir years of debate.  US Brigadier General Philip St. George Cooke ordered 2nd, and 5th, US Cavalry regiments to slow the rapidly advancing Confederates.  This would quickly turn into a rout, with Hood's Rebels capturing  fourteen guns, and killing many cavaliers.  This brought to an end, the bloodiest day of fighting, thus far in the Civil War.

Campaign: The Seven Days

Outcome: Confederate Victory

Troop Strengths
Union: 39,000
Confederate: 56,000

Casualties (estimated):
Union: 6,837 (killed, wounded or missing/captured)
Confederate: 8,750 (killed, wounded or missing/captured)

Battle Aftermath:
While Robert E. Lee suffered more casualties, at Gaines' Mill, than Fitz John Porter, this was his first significant victory as a field commander.  He was able to push George McClellan's Army of the Potomac from the "Gates of Richmond," to the southeast, thus depriving McClellan of the siege, he so wanted.  There would be more battles, and many more casualties, before the Seven Days were over, but Robert E. Lee would succeed in pushing the Army of the Potomac from the peninsula, and back to Washington D.C. 
 Close Window