Earle Davis Gregory was born in Clayville, Virginia on October 18, 1897. His father served as a telegrapher for the Richmond and Danville Railway, eventually transferring to Chase City, Virginia as a dispatcher in 1901. Upon completion of his freshman year, Gregory entered the Fork Union Military Academy from 1912 until the summer of 1915, when Gregory returned to Chase City and joined Company E, 2nd Regiment, Virginia Volunteers.

On October 8, 1918, Gregory's unit was committed to battle at Bois-de-Consenvoye, north of Verdun, France during the outset of the United States involvement in World War I. On his first day of battle, Sergeant Gregory's unit was halted by incessant machine gun fire by German forces. Gregory abandoned his position and charged the machine gun, destroying it with a mortar round along with single-handedly capturing a howitzer and 22 German prisoners. His actions and overall valiance earned Gregory the Congressional Medal of Honor, the only Virginian to be awarded the Medal during World War I.

Three days later, Gregory and his unit were attempting to take an enemy trench line when an artillery shell landed on his unit, wounding Gregory in his leg from shrapnel. Gregory was hospitalized for six months, partly in France before being shipped to Camp Lee, Virginia. He was discharged on April 25, 1919, and four days later Gregory was awarded the Medal of Honor at a ceremony on the Camp's parade field.

Gregory enrolled in Virginia Polytechnic Institute in September of that year. Entering under a disabled veteran's program, Gregory was accepted into the Corps of Cadets in spite of his war wound. He served as Cadet 1st Sergeant during his junior year and Cadet Captain of Company A during his senior year, in addition to being elected to class president twice and president of the student body his senior year.

Gregory was a life-long member of the American Legion, Disabled American Veterans and a Master Mason. He died on January 6, 1972 in Tuscaloosa, Alabama. The Virginia Tech Corps of Cadets renamed the "Pershing Rifles" drill team in his honor, now known as the "Gregory Guard," an elite drill and marching unit.