Why Did The South Lose Gettysburg, The Most Decisive Battle Of The Civil War?

As fighting raged to the northwest of Gettysburg on the first day, Union forces arrived on Cemetery Hill just to the southeast of the town. Instead of pushing forward to join the fight, the Union chose instead to secure the high ground, which was the most defensible position. 

This decision would set the stage for the next two days of fighting, where the Union would try to hold this tactical advantage against Confederate attacks. The Union forces arranged themselves in a fishhook shape along Cemetery Ridge, Culp's Hill, Little Round Top, and Big Round Top.

After the Union cavalry delayed the initial Confederate advance on the first day, the first wave of Union reinforcements was unable to hold the line to the north of Gettysburg. An attack by General Jubal Early under Lieutenant General Richard Ewell on the northeastern Union flank caused the line to collapse. The Union retreated to a position on Cemetery Hill, which had already begun forming. 

Lee had given Ewell discretionary authority to attack the position on Cemetery Hill, but Ewell chose not pursue the advantage. Instead, he opted to wait for Longstreet's troops to arrive.

As Union reinforcements began to arrive that evening, the numerical advantage the Confederates had gained during the day was lost.

While some consider the Confederate attack on the third day of fighting to be a massive tactical blunder on Lee's part, others point out how uncharacteristic it was of Lee, given his record. One of the strangest aspects of the direct attack on the Union center - a maneuver that would become known as Pickett's Charge - is that the attack only utilized a small fraction of the troops available. Less than 15,000 troops were involved when the total forces available were several times greater than that.

Pickett's Charge consisted of nine brigades commanded by Longstreet, three of which were composed of troops from General George Pickett's division. These fresh troops, who had yet to see action, would spearhead the attack. The Confederate troops had to march across three-quarters of a mile of open field - right in front of the center Union line.

Under heavy artillery fire, the Confederates advanced. On top of the ridge, some 10,000 Union troops waited behind a stone wall for the Confederates to get into range. When they did, it was carnage. The Confederate charge was able to briefly break the Union line and advance onto Cemetery Ridge, but they were unable to hold their ground. The Confederates retreated, and suffered an almost 50% casualty rate. Pickett's division lost two-thirds of its men.

The fact that Lee held so many troops back in reserve indicates to some historians, such as Tom Carhart, that he had an entirely different plan for how the operation should play out. The question remains: Given how close Pickett's Charge came to dividing the Union line, would it have succeeded if more men were committed to it? Or was a direct attack simply a mistake by Lee that was doomed from the start?

On the second day of the battle, Lee ordered Longstreet to attack the left Union flank while Ewell and Hill launched secondary attacks on the right flank. The order didn't come until 11:00 am, however, due to disagreements among Lee, Longstreet, and Ewell. By the time Longstreet's troops were in position, it was almost 4:00 pm.

While Longstreet was able to take ground from Union General Daniel Sickles - who had advanced forward to Peach Orchard, the Wheat Field, and Devil's Den - the Union position on Little Round Top held. Meanwhile, Hill and Ewell's attacks began late, with Ewell's not commencing until 6:00 pm.

While Ewell did manage to take some ground, the Confederate advance ultimately stalled.

On July 2, 1863, at the extreme left flank of the Union line, the 20th of Maine under Colonel Joshua Chamberlain was positioned on Little Round Top. His orders were to hold the position at all costs. The battle raged throughout the day, and the regiment was running out of ammunition. As the Confederates began another attack on the position, Chamberlain ordered his troops to fix bayonets and charge. The desperate charge worked, and the Confederates either surrendered or withdrew.

It should be noted that Chamberlain wasn't the only Union officer to lead a desperate charge to save Little Round Top. Earlier in the day, Colonel Patrick O'Rorke led his 140th New York into a separate charge and engaged the Confederates hand to hand. Unlike Chamberlain, O'Rorke did not survive the heroic maneuver.

Before the Battle of Gettysburg commenced, Stuart had taken the Confederate cavalry on a long sweep to position it between the Union forces and Washington, DC. Stuart's orders were to screen for Lee's troops, but instead, Stuart went off on a raid and was subsequently delayed. This left the main force of the Confederates, already positioned deep inside enemy territory, without any cavalry.

The importance of this was twofold. First, without Stuart's cavalry, the Confederate forces lacked intelligence data. Without the means to properly scout enemy positions, General Robert E. Lee was left guessing what the enemy was doing during critical moments in the battle. Second, without Confederate cavalry available on the first day of the battle, General John Buford's Union cavalry was able to delay the Confederates long enough for initial reinforcements to arrive.

Stuart's cavalry didn't arrive until July 2, the second day of the battle. By then, they were already exhausted from the journey.