Capehart enlisted in the Union Army and was commissioned captain and placed in command of Company A, 1st West Virginia Cavalry.

On July 4, 1863, Capehart's regiment charged down a mountainside at night during a thunderstorm, attacking and capturing a retreating Confederate wagon train.

His brother, General Henry Capehart was also awarded the Medal of Honor for his actions in the Civil War.

[1] For The President of the United States of America, in the name of Congress, takes pleasure in presenting the Medal of Honor to Major Charles E. Capehart, United States Army, for extraordinary heroism on 4 July 1863, while serving with 1st West Virginia Cavalry, in action at Monterey Mountain, Pennsylvania.

While commanding the regiment, Major Capehart charged down the mountain side at midnight, in a heavy rain, upon the enemy's fleeing wagon train.