Army of the Mississippi

At its creation, the army consisted of 2 divisions of infantry for service along the Mississippi River.

When General Pope began to move against New Madrid, Missouri, the army was expanded with units from neighboring military districts.

The army now totaled 5 divisions commanded respectively by David S. Stanley, Schuyler Hamilton, John M. Palmer, Eleazar A. Paine and Joseph B. Plummer.

Its position there was strengthened by two divisions from the Army of West Tennessee and fought at the battles of Iuka and Corinth.

Maj. Gen. Ulysses S. Grant did not like McClernand and after Sherman and Admiral Andrew H. Foote both voiced their opinions that McClernand was unfit to command, Grant personally took command of the expedition against Vicksburg and the old XIII Corps and XV Corps were returned to the Army of the Tennessee on January 12, 1863.

General John Pope was the first commander of the Army of the Mississippi
General John McClernand was the final officer to use the name "Army of the Mississippi" for a field unit