Sherman's objective at Resaca was to cut the Western & Atlantic Railroad

Both the Union and Confederate soldiers in Northern Georgia depended on the Western & Atlantic Railroad for their survival. It was a reliable source of supplies for Gen. Joseph E. Johnston and Maj. Gen. William T. Sherman exploited it to provide his force with food and munitions as they advanced deeper into the territory of the enemy. By cutting the rail line south of Johnston and securing it for himself in the north, Sherman knew he could force Johnston into retreat. Sherman was well aware of these logistical issues.

The Confederate army had established a formidable defensive line north of Dalton and along Rocky Face Ridge during the winter of 1863–1864, Sherman did not intend to attack the Confederate position like Grant was planning to do against Lee in Virginia, despite the fact that the United States had a significant numerical advantage (110,000 to 53,800). Instead, he intended to deploy a section of his force under Maj. Gen. James B. McPherson to the south, beyond the Rebels' left flank, and through the undefended Snake Creek Gap in order to divert Johnston. From there, McPherson was supposed to advance to the east and cut the rail line close to Resaca, compelling Johnston to give up his Dalton defenses.