The Harvey C. Barnum, Jr. (DDG 124) is the 74th Arleigh Burke-class guided-missile destroyer and the first ship in the United States Navy named in honor of retired Marine Corps Col. Harvey C. Barnum, Jr., who received the Medal of Honor for heroism displayed during an action outside Ky Phu, Quang Tin Province, Vietnam, in December 1965.

May 21, 2021 The keel authentication ceremony for the future USS Harvey C. Barnum, Jr., was held at the Bath Iron Works shipyard.

July 29, 2023 The Pre-Commissioning Unit (PCU) Harvey C. Barnum, Jr., was christened during a 10.30 a.m. EDT ceremony at Bath Iron Works in Bath, Maine. Ms. Martha Hill, the wife of the ship's namesake, served as the sponsor.

October ?, The Harvey C. Barnum, Jr., was launched for the first time from a floating dry-dock and moored pierside on Bath Iron Works shipyard.

July 17, 2025 PCU Harvey C. Barnum, Jr., moored at Pier 3 on Bath Iron Works shipyard after a two-day underway for Builder's (Alpha) trials; Underway again from Aug. 11-14; Underway for acceptance trials on Sept. 17; Moored at Ocean Gateway Pier II in Portland, Maine, for an overnight stop on Sept. 18; Returned to Bath on Sept. 19.

November 17,  U.S. Navy officially accepted delivery of the future USS Harvey C. Barnum, Jr., during a brief ceremony aboard the ship.

March 4, 2026 PCU Harvey C. Barnum, Jr., commanded by Cmdr. Benjamin R. Cantu, departed Bath, Maine, for the last time en route to Norfolk, Virginia; Moored at Pier 2N in Naval Station Newport, R.I., on March 5.