Returning to the field in the fall of 1862, Tilghman became a brigade commander in Mansfield Lovell's division of Earl Van Dorn's Army of the West, following the Second Battle of Corinth. In the Vicksburg Campaign of 1863, he was hit in the chest by a shell and killed in the Battle of Champion Hill. He is buried in Woodlawn Cemetery, The Bronx, New York City, where his body was moved in 1902 to be interred beside his wife who had moved to the city.