The French battleship �Jean Bart� together with the twin �Richelieu� was among the largest and most modern ships of this class that served in the Marine Nationale. Their construction was based on the experience gained during the construction of Dunkerque battleships, smaller and less armed units, but quite modern for their times. A characteristic feature of the aforementioned ships, including the �Jean Bart�, was the unusual layout of the main artillery concentrated in two four-barrel turrets located in the fore part, while medium caliber artillery was located in the stern part. This, in combination with the massive body of the command tower and the chimney �hidden� in the rest of the superstructures, created an amazingly presented silhouette of a beautiful and very dangerous ship. �Jean Bart� was built at the Ateliers et Chantiers de Saint-Nazarie (Penho�t) shipyard in Saint-Nazarie. The keel was laid on December 12, 1936. The ship was launched on March 6, 1940.