Why Didn't Confederate General Johnston Attack Grant During the Siege of Vicksburg?

The Strategic Failures of Confederate General Johnstons: A Case Study of the Siege of Vicksburg
In what is regarded as one of the most crucial episodes of the American Civil War, Confederate General Joseph E. Johnston's decision not to attack Union General Ulysses S. Grant during the Siege of Vicksburg in 1863 was influenced by a complex interplay of strategic, logistical, and political factors. This article explores the reasons behind Johnston's decision and the consequences it had on the outcome of the siege.

Strategic Disadvantages and Logistical Challenges

Johnston faced significant logistical challenges and a lack of adequate troops to launch a strong offensive against Grant’s well-entrenched forces. Grant had a robust position, and any attack would likely have been costly for Johnston's forces. The city of Vicksburg was strategically positioned on a high bluff overlooking the Mississippi River, making it a formidable target. At the time of the investment, Grant had three army corps—Sherman’s XV Corps to the north, McPherson’s XVII Corps to the east, and McClernand’s XIII Corps to the southeast—each occupying strategic positions. This formation was effective in containing Johnston's advancing forces.

Lack of Coordination and Confusion

Johnston was not in direct command of the Confederate forces at Vicksburg, which were under the command of General John C. Pemberton. There was a significant lack of coordination between Johnston and Pemberton, leading to confusion and missed opportunities for a concerted effort against Union forces. Frustratingly, Johnston’s forces were scattered and not fully prepared for a coordinated assault. Forces had to be consolidated from various locations, and the logistical infrastructure required to support them was strained. Johnston had to gather troops to reinforce Pemberton, but they were not yet ready for a fully coordinated strike.

Timing and Readiness

Johnston was not fully prepared to launch an attack, and he was acutely aware of the potential for Union reinforcements which could have complicated any attack. By the time he was able to coordinate his forces and gather sufficient reinforcements, Grant had already dug in and reinforced his position with additional troops. When Johnston finally began to move west, it was too late. By the time he had traveled a half-hearted 15 miles to Brownsville and Midway, Grant had already secured his position and prepared for the long-term siege.

Political and Military Constraints

Johnston was deeply concerned about the political ramifications of a failed attack. A defeat could have had dire consequences for the morale of the Confederate army and the Southern cause. He prioritized the preservation of his forces over a potentially risky assault. The Confederate high command did not react with the same urgency as Grant, and the lack of coordinated efforts further elongated the siege. Johnston’s forces, spread out over a wide arc, faced significant challenges in re-establishing logistical support and consolidating their forces.

Grant's Strategy and the Final Consequences

Grant was well aware of the strategic importance of Vicksburg and had laid siege to the city effectively cutting off supplies and reinforcements. This made the prospect of a relief effort from Johnston even more challenging. Grant realized the urgency of the situation and launched two assaults, attempting to force the immediate capitulation of the city. He also called up resources and reinforcements, bringing the total number of his forces to nearly 90,000. On the other hand, Johnston's force of 25,000 was spread out over an arc 50 miles from the city, making it difficult to mount a successful coordinated attack.

When Johnston received word of the surrender on July 4, 1863, it was already too late. The defenders had no other option but to surrender, which ultimately led to the fall of Vicksburg. This significant turning point in the Civil War marked a pivotal shift in the dynamics of the conflict, solidifying Union control over the Mississippi River and its crucial supply lines.

The failure to relieve Vicksburg had profound consequences, with Pemberton negotiating terms of surrender that included the personal horses and sidearms of his officers, a condition which almost included the officers' Confederate-owned slaves. The lesson learned from this episode underscores the importance of strategic planning, coordination, and the significance of timely military action in the outcome of major sieges.