Charles Garrison Harker was a brigadier general in the Union Army during the American Civil War. He was killed in action at the Battle of Kennesaw Mountain in northern Georgia during the Atlanta Campaign. Fort Harker in Kansas, an active garrison of the United States Army from 1866 to 1872, was named in his honor. The Charles G. Harker School in the Swedesboro-Woolwich School District, New Jersey, is named in his honor.

The Battle of Kennesaw Mountain was fought on June 27, 1864, during the Atlanta Campaign of the American Civil War. It was the most significant frontal assault launched by Union Maj. Gen. William T. Sherman against the Confederate Army of Tennessee under Gen. Joseph E. Johnston, ending in a tactical defeat for the Union forces. Strategically, however, the battle failed to deliver the result that the Confederacy desperately needed—namely a halt to Sherman's advance on Atlanta.