Campbell Dallas Emory, eldest son of Matilda Wilkins (née Bache) and Major General William H. Emory, was born on December 23, 1839, in Philadelphia, Pennsylvania. His great-great-grandfather was Benjamin Franklin. Like his father, Campbell Emory graduated from the United States Military Academy, West Point, on May 6, 1861. He graduated as a second Lieutenant in the 6th United States Infantry Regiment, he transferred to the 9th United States Infantry Regiment; where he rose in rank throughout the American Civil War. From December 1863 to the end of the war, Capt. Emory served as the Aide de Camp to Major General George Meade.
