March 26, 1864

McPherson takes over the Army of the Tennessee
General James B. McPherson assumes command of the Union Army of the Tennessee after William T. Sherman is elevated to commander of the Division of the Mississippi, the overall leader in the West.

McPherson was born in Ohio in 1828. He graduated first in his class from West Point in 1853. He joined the engineering corps as a second lieutenant, and he spent the prewar years in New York City and Alcatraz Island in California. When the war began, McPherson was transferred to the East and promoted to captain. He was disappointed when he was assigned to command the forts of Boston Harbor, as the young officer yearned for combat. McPherson contacted General Henry Halleck, commander of the Department of the Missouri and a former acquaintance in California. Halleck summoned him to St. Louis, where McPherson helped set up recruiting stations and inspecting defenses in the state.

McPherson was transferred to General Ulysses S. Grant's command on February 1, 1862, just as Grant was launching an expedition against Forts Henry and Donelson in Tennessee. McPherson's work in analyzing the defenses of Fort Donelson earned him the respect of Grant, and McPherson's star rose rapidly after the Battle of Shiloh. McPherson fought with distinction, and he was promoted to colonel. Two weeks later, he became a brigadier general. After his actions at the Battle of Corinth, Mississippi, in October 1862, McPherson was again promoted, this time to major general. In December, he capped an amazing year by taking command of the XVII Corps in Grant's Army of the Tennessee.

McPherson served as corps commander throughout 1863, ably leading his men at Vicksburg and Chattanooga. Grant's promotion to general-in-chief of all Union forces created a chain reaction of promotions. Grant left for Washington and Sherman assumed command in the West while McPherson inherited the Army of the Tennessee. This force was not an independent command, as it was one of three armies under Sherman's command during the Atlanta campaign of 1864. When the campaign reached Atlanta in July 1864 after three hard months of fighting, McPherson was charged with attacking Confederate forces on the northeast side of Atlanta. At the Battle of Peachtree Creek on July 22, McPherson was directing operations when he and his staff emerged from a grove of trees directly in front of the Confederate line. They were ordered to surrender but McPherson turned his horse and attempted to escape. He was mortally wounded, becoming the highest-ranking Union general killed in the war.