Jacob Hopping enlisted for a 3-year service on September 15, 1861. Hopping served as Corporal on Company K in the 7th New Jersey Infantry. He was mortally wounded in his left thigh during the fighting on July 2, 1863 at the battle of Gettysburg, Pennsylvania. He lingered until his death on July 16th, 1863.

He is buried in Evergreen Cemetery in Gettysburg, PA.