John Mitchell Vanderslice (August 31, 1846 - March 12, 1915) was a United States soldier who fought for the Union Army during the American Civil War as a member of the 8th Pennsylvania Cavalry.

He received his nation's highest award for valor, the U.S. Medal of Honor, for being the first man to reach the rifle pits of the Confederate States Army during a charge made by his regiment on CSA fortifications in the Battle of Hatcher's Run, Virginia on February 6, 1865.

He and his brothers, Thaddeus (1841–1907) and Theodore (1848–1924), were sons of Marcus Vanderslice (1813–1876), and were raised on "a farm adjoining Valley Forge Campground,[5] and educated at the Freeland Seminary, a Mennonite preparatory school for boys which was located in Collegeville, Pennsylvania.

[9] He had joined just in time to fight with the 8th Pennsylvania Cavalry during one of the Union Army's most significant phases of duty — the Overland Campaign in Virginia commanded by Lieutenant-General Ulysses S. Grant.

On February 6, 1865, while fighting with the 8th Pennsylvania Cavalry in the Battle of Hatcher's Run, he became the first man to reach the rifle pits of the Confederate States Army during a charge made by his regiment on CSA fortifications.

[13][14] Following his honorable discharge from the military, Vanderslice returned home to Pennsylvania, where he completed his studies at the Freeland Seminary, trained to become a lawyer, and became active in politics as a member of the Republican Party.

According to historian Tom Huntington, "Vanderslice persuaded a GAR post in Erie, Pa., to erect the first monument on the battlefield, a small stone on Little Round Top honoring Strong Vincent, a Pennsylvania brigade commander mortally wounded on the battle’s second day."