The St. Louis (LCS 19) is the 10th ship in the Freedom-class littoral combat ships and the seventh ship in the United States Navy to be named after St. Louis, the largest city in the state of Missouri.

May 17, 2017 The keel authentication ceremony for the future-USS St. Louis was held at the Fincantieri Marinette Marine Corp. Shipyard in Marinette, Wisconsin.

December 15, 2018 The Pre-Commissioning Unit (PCU) St. Louis was christened and launched during a 10 a.m. CST ceremony at Marinette Marine Shipyard. Mrs. Barbara B. Taylor, the wife of Andrew C. Taylor, Chairman and CEO of Enterprise Holdings, served as sponsor of the ship.

November 8, 2019 The St. Louis returned to Marinette shipyard after a one-day underway for Builder's (Alpha) trials on Lake Michigan; Day-long underway on Nov. 18; Brief underway on Nov. 26; Day-long underway for acceptance trials on Dec. 11.

February 6, 2020 U.S. Navy accepted delivery of the future USS St. Louis during a short ceremony aboard the ship.

June 12, PCU St. Louis (Crew 121 - Blue), commanded by Cmdr. Kevin R. Hagan, returned to Marinette shipyard after a one-day underway on Lake Michigan; Departed Marinette for the last time on June 20; Transited the Detroit River southbound on Sunday evening.

June 22, The St. Louis moored at Dock 28W in Port of Cleveland, Ohio, for a two-day port call; Transited the Welland Canal on June 25; Moored at Port of Ogdensburg, N.Y., to refuel from June 26-27; Brief stop approximately 3 n.m. south of Les Esqoumins, Quebec, just after midnight, on June 29; Moored at Pier 32N on Naval Submarine Base New London in Groton, Conn., from July 5-7; Moored at Pier 16S on Joint Expeditionary Base Little Creek-Fort Story, Va., from July 9-15.

July 9, The St. Louis moored at Wharf F2 in its homeport of Naval Station Mayport, Fla., for the first time; Moved to Wharf C2 on Aug. 5.

August 8, USS St. Louis was commissioned during a private 10 a.m. EDT ceremony at Charlie Wharf on Naval Station Mayport.

August 24, The St. Louis moved from Wharf C2 to Wharf D3 on Naval Station Mayport; Underway in the Jacksonville Op. Area from Sept. 2-4; Underway again from Sept. 8-13, Sept. 16-18 and Oct. 4.

October 6, USS St. Louis moored at Quay Wall West on Joint Expeditionary Base Little Creek-Fort Story, Va., for a brief stop before underway in the Virginia Capes Op. Area; Moored at Wharf D2 in Naval Station Mayport on Oct. 11; Moved to Wharf C2 on Oct. 16; Underway again on Oct. 21.

October 23, The St. Louis moored at Pier 16S on Joint Expeditionary Base Little Creek-Fort Story for a brief stop before conducting Combat Systems Ship's Qualification Trials (CSSQT) in the Virginia Capes Op. Area; Moored at Quay Wall West from Oct. 26-27.

October 29, The St. Louis moored at Wharf D2 on Naval Station Mayport; Moved to Wharf F2 on Dec. 4; Underway again on Dec. 11; Moored at Naval Weapons Station Yorktown, Va., for ammo onload from Dec. 14-16.

December 18, USS St. Louis moored outboard the USS Billings (LCS 15) at Wharf D4 on Naval Station Mayport; Moved to Wharf B3 for a brief stop on Jan. 5; Moved to Wharf D2 on Jan. 11.

January 21, 2021 The St. Louis moored at Wharf C1 on Naval Station Mayport after a brief underway off the coast of Jacksonville; Day-long underway on Feb. 17; Day-long underway for Final Contract Trials (FCT) on Feb. 26.

March 4, USS St. Louis moved "dead-stick" from Naval Station Mayport to BAE Systems Jacksonville Ship Repair facility, for a Post Shakedown Availability (PSA).

July 1, Cmdr. Eric D. Turner relieved Cmdr. Kevin R. Hagan as CO of the LCS Crew 121 during a change-of-command ceremony at Naval Station Mayport's chapel.

February 4, 2022 The Rotational LCS Crew 121 (Blue) assumed command of the St. Louis during a crew exchange ceremony aboard the ship.

August 12, Cmdr. John Bear relieved Cmdr. Hiram Andreu as CO of the LCS Crew 120 (Gold) during a change-of-command ceremony on Naval Station Mayport.

August 26, The Rotational LCS Crew 120 (Gold) assumed command of the St. Louis during a crew exchange ceremony on board the ship.

September 8, USS St. Louis moved "dead-stick" from BAE Systems shipyard to Wharf D4 on Naval Station Mayport; Moved to Wharf D2 on Nov. 18; Underway for sea trials from Nov. 21-22 and Dec. 12-13.

January 13, 2023 Cmdr. Jonathan C. Williams relieved Cmdr. Eric D. Turner as CO of the LCS Crew 121 (Blue) during a change-of-command ceremony on board the ship.

January 17, The St. Louis moved from Delta Wharf to Wharf C2 on Naval Station Mayport for ammo onload; Moved back to Wharf D2 on Jan. 18; Day-long underway on Feb. 8; Moved to Wharf C1 on March 6; Moved to Wharf D2 on March 27; Brief underway off the coast of Jacksonville on April 12; Underway again from April 13-14 and Oct. 2-3.

November ?, Cmdr. Jonathan C. Williams assumed command of the St. Louis during a crew combination ceremony on board the ship.

January 25, 2024 USS St. Louis moored at Wharf D2 on Naval Station Mayport after a two-day underway in the Jacksonville Op. Area; Underway again from Jan. 27-31 and March 15-1?; Moved to Wharf C1 for a brief stop to onload ammo on March 26.

May 17, Cmdr. Timothy J. Orth relieved Cmdr. Jonathan C. Williams as CO of the St. Louis during a change-of-command ceremony on board the ship.

May 19, USS St. Louis moored at Wharf D2 on Naval Station Mayport after a brief underway off the coast of Jacksonville; Underway again on June 7; Moored at Wharf C2 on June 8.

June 15, USS St. Louis, with an embarked Helicopter Maritime Strike Squadron (HSM) 50 Det. 4, departed Mayport for its maiden deployment in support of counter-illicit trafficking operations.

July ?, The St. Louis moored at Berth 8 in Port of Ponce, Puerto Rico, for upkeep.

August 6, USS St. Louis recently moored at Port of Cristobal in Colon, Panama, for a routine visit before transiting the Panama Canal; Conducted a replenishment-at-sea with the BAP Tacna (ARL 158), while underway off the coast of Peru, on Aug. 26.

September 1, USS St. Louis moored at Abrigo Pier in Valparaiso Naval Base, Chile, for the in-port phase of a multinational exercise UNITAS LXV; Underway for at-sea phase on Sept. 5; Moored at Abrigo Pier again from Sept. 11-1?.

October 1, The St. Louis moored at Fuerte Amador Cruise Terminal on Flamenco Island, Panama, on late Tuesday evening, for a two-day liberty port visit to Panama City; Participated in a PHOTOEX with the JS Kashima (TV 3508) and JS Shimakaze (TV 3521) on Oct. 4; Moored at Fuerte Amador Cruise Terminal again from Oct. 7-8 and Oct. 12-13.

October 13, USS St. Louis commenced the northbound transit of Panama Canal on Sunday evening; Moored at Pier 16E, Port of Cristobal in Colon, Panama, from Oct. 14-15; Moored at Victor Pier in Naval Station Guantanamo Bay, Cuba, for upkeep on Oct. 2?.