Origins
On January 10, 1862, President Jefferson Davis attempted to coordinate Confederate military operations west of the Mississippi River by placing Major General Earl Van Dorn in command of the newly created Trans-Mississippi District of Department Number 2. On January 29, Van Dorn assumed command, established his headquarters at Pocahontas, Arkansas, and began organizing his forces, composed largely of soldiers from the Missouri State Guard. He also developed ambitious plans to sweep through Missouri, capture St. Louis, and threaten Union operations in Kentucky. His first order of business was to drive Brigadier General Samuel R. Curtis and the Union Army of the Southwest out of Arkansas.
Battle of Pea Ridge
On March 4, 1862, Van Dorn started north with approximately 16,000 troops, which he named the Army of the West. After three days of forced marching through harsh winter weather, the Confederates confronted Curtis’ army. The cold, hungry, and exhausted Rebels were no match for the Federals who were well-entrenched on high ground known as Pea Ridge. Two days of futile combat forced Van Dorn to withdraw.
Following the Confederate defeat at the Battle of Pea Ridge (March 6 – 8, 1862), Van Dorn moved the remnants of his tattered Army of the West across the Mississippi River where they served under the overall command of Major General P. G. T. Beauregard during the Siege of Corinth (April 29 to May 30, 1862).
Change in Command
On June 20, Confederate officials transferred Van Dorn to the Department of Southern Mississippi and East Louisiana. Command of the Army of the West temporarily transferred to Major General John P. McCown. Two weeks later, on July 3, 1862, Confederate officials replaced McCown with Major General Sterling Price.
Battle of Iuka
In July 1862, Confederate Major General Braxton Bragg marched his Army of the Mississippi from Tupelo, Mississippi, to Chattanooga, Tennessee, to make preparations for his invasion of Kentucky known as the Confederate Heartland Campaign. When Bragg left Chattanooga one month later, Price began moving the Army of the West north in support.
By September 13, 1862, Price reached a small Union supply depot on the Memphis & Charleston Railroad at the town of Iuka, Mississippi, approximately twenty miles east of Corinth. As Price’s army advanced on the Union garrison, the Federal commander, Colonel Robert C. Murphy, set fire to the Union supplies, abandoned his post, and marched his 2,000-man brigade back to Corinth.
Now in control of Iuka, Price settled in to await Earl Van Dorn’s 7,000-man force to arrive from the Department of Southern Mississippi and East Louisiana. The two generals intended to unite their armies and to attack Union supply and communication lines as they moved north to join Bragg.
Before the Rebels could unite the two armies, Major General Ulysses S. Grant dispatched two Federal forces commanded by Major General William S. Rosecrans and Major General Edward O. C. Ord to attack Price simultaneously and retake the supply depot Iuka. Although the assault was uncoordinated and did not go according to plan, Grant’s forces prevailed.
The Battle of Iuka (September 19, 1862) was a hollow Union victory. Grant’s forces regained the supply depot while suffering fewer casualties; nonetheless, most of the Army of the West escaped overnight using a road that Rosecrans had failed to secure.
Merger
Price’s escape at Iuka enabled him to complete his rendezvous with Van Dorn. On September 28, 1862, they merged their forces to form the Army of West Tennessee, under Van Dorn’s command. The merger relegated Price to the command of a corps that informally kept the name, Army of the West.