On May 7, 1864, Federal forces under Maj. Gen. W.T. Sherman began the campaign for Atlanta by seizing Tunnel Hill. Howard's 4th A.C., having marched from Catoosa Springs, drove Wheeler's Cav. from the R.R. tunnel south to Mill Creek Gap. Palmer's 14th A.C., moving from Ringgold along U.S. Highway 41, supported Howard on his right and extended the Federal front to Mill Cr. Gap, where its right joined the left of the 20th A.C. in Dogwood Valley. These operations were designed to engage the Confederate forces at Dalton while McPherson's army moved from the west to Snake Creek Gap, 18 miles south of Tunnel Hill.