John Sullivan (1839 – June 23, 1913) was a Union Navy sailor during the American Civil War who received America's highest military decoration, the Medal of Honor, for his actions while serving aboard the USS Monticello. Sullivan was born in 1839 in New York City. From June 23 to 25, 1864, he showed "gallantry and coolness" during a reconnaissance mission against Confederate defenses in the harbor of Wilmington, North Carolina. For these actions, he was issued the Medal of Honor six months later, on December 31, 1864. He is interred at Harmony Grove Cemetery in Portsmouth, New Hampshire.