Explanation: Maj. Gen. Ulysses S. Grant laid out immediate plans for a campaign south against Vicksburg to capture the important waterway and port.
With his October 16, 1862 appointment as commander of the Department of the Tennessee, Maj. Gen. Ulysses S. Grant laid immediate plans for a campaign south against Vicksburg, Mississippi.
On October 20, Maj. Gen. John A. McClernand secured command of the short-lived Army of the Mississippi, with the express mission of seizing Vickdburg. A dubios political appointment made by President Lincoln, its effects was soon nullified by political pressure within the Regular Army. Grant proceded with his campaign plans, never overtly acknowledging McClernand's. Assuming departmental command on October 25, by November 8, Grant had his troops gathered around La Grange, Tennessee, north of the Mississippi state line, just a few miles west of Grand Junction, Tennessee. His plans was to follow the line of the Mississippi Central Railroad south toward Vicksburg. Suppliea were to come south from Columbus, Kentucky, by way of the Tennessee & Ohio Railroad and at Grand Junction switch onto the Mississippi Central track for the journey south. Maintaining lines of communications and supply along the railroads would prove to be the failure of this campaign.
With little force to oppose Grant, the Confederate commander at Vicksburg, Lt. Gen. John C. Pemberton, had to rely on Maj. Gen. Earl Van Dorn's troops, recently defeated at Corinth, and on action against the Union rear supplied by Brig. Gen. Nathan B. Forrest. By December 1, Grant's troops were facing Confederates, in shallow trenches, along the Tallahatchie River, north of Oxford, Mississippi, 35 miles south of Grand Junction. A large Union supply depot had been established at Holly Springs, Mississippi, a little over 15 miles north along the Mississippi Central. By December 2, the Union troops had occupied Oxford and dispatched cavalry in pursuit. Van Dorn's cavalry, serving as rear guard, stopped these Union cavalry at the engagement at Coffeeville, Mississippi on December 5, and forced thier return to Oxford. Union troops continued probing southward during the next 2 weeks.
Pemberton was to rely on Gen. Joseph E. Johnston for supervision in the defense of Vicksburg. Johnston had been given this task on November 24, but little advice had been forthcoming. When Pemberton requested aid from Gen. Braxton Bragg in Tennessee, Bragg told Pemberton that he was preparing for his Murfreesboro campaigning (which would end in the Battle of Stones River) and could offer no material assistance; but he could order Forrest's cavalry to hit Grant's supply lines. This was Forrest's Second Raid. Begun on December 11, it destroyed great portions of Tennessee rail line and threatened Grant's Columbus, Kentucky, railhead. Grant responded by switching his base of supply to Memphis, Tennessee. He then sent his materials east on the Memphis & Charleston Railroad to Grand Junction. However, on December 20, Van Dorn led 3,500 cavalry from Grenada, south of Grant's lines, and attacked the Union general's Holly Springs supply base. The Holly Springs Raid resulted in the loss of more than $ 1.5 million in Union supplies. Col. Benjamen H. Grierson pursued Van Dorn in vain for days before the Confederates easily reentered Southern lines at Grenada.
Grant realized the error of trying to maintain his supply and communication along rail lines., and within a week of the Holly Springs raid, withdrew most of his forces to La Grange. This ended his 1st Vicksburg Campaign. determined to keep up relentless pressure on Vicksburg, he initiated the first of many waterborne invasion plans, which brought on the battle at Chickasaw Bluffs.