During the Spanish-American War, Fort McPherson served as a major military hospital and held a small number of prisoners from the Cuban campaign. At the end of the war, activity at the post slowed, and the Sixteenth Infantry Regiment, which had been stationed in Atlanta just after the Civil War, assumed garrison duty.
The Seventeenth Artillery Regiment was assigned garrison duty from 1902 until 1917 and was frequently deployed to Cuba, as well as to Texas and Mexico to help subdue the Mexican bandit Pancho Villa.
On August 1, 1863, he was made a Brigadier General in the regular army, and was given command of the Army of the Tennessee on March 26, 1864 after William T. Sherman was promoted to command all armies in the West.
McPherson’s army made up the right wing of Sherman’s force as he moved against Atlanta beginning in May of 1864. He and his troops participated throughout the Atlanta Campaign, trying to outmaneuver Confederate forces under Joseph E. Johnston. On May 9, 1864, McPherson tried to flank and destroy Johnston at the Battle of Rocky Face Ridge, but his 25,000-man column was thwarted by a blocking force of some 4,000 Confederates. Hearing of this defeat, Sherman told McPherson that he had “missed the opportunity of a lifetime.” McPherson’s army also suffered heavily while assaulting the steep slopes of Kennesaw Mountain on June 27, 1864.