Richelieu, her sister ship Jean Bart, and the unfinished Clemenceau and Gascogne, were intended to counter the growing threat of the Italian Navy. Comparing favourably with contemporary rivals. The twin turret, four gun arrangement for the main battery of eight 380mm (15") guns was unusual. An advantage was that the entirety of the main artillery could fire forwards at an angle where the ship made the smallest possible target. The Richelieu class were the most powerful battleships ever built in France.
The keel was laid in October 1935 in Brest. Richelieu was launched in January 1939, and sea trials began in January 1940
After the German offensive broke through the French defences in 1940 the incomplete Richelieu under the command of Captain Marzin hastily left Brest on 18 June under her own power, escorted by the Adroit class destroyers Fougueux and Frondeur, arriving at Dakar on 23 June. Transferring to Casablanca two days later she was shadowed by a powerful British battle group but returned to Dakar on 28 June and although only 95% complete commissioned on 15 July 1940.
The armistice between France and Germany prompted British anxiety that the French Navy would be taken over by the Germany. This led to attacks by Swordfish torpedo bombers from the British aircraft carrier HMS Hermes on July 8, 1940, after the attack on the French fleet at Mers el-Kebir. A torpedo hit below the armoured deck disabled the starboard propulsion shaft on Richelieu and flooding caused her stern to touch bottom. She was pumped out after a few days, however, and made seaworthy for emergencies.
On 24 September, Richelieu fought against Allied naval forces at the Battle of Dakar. There was a gunnery duel between Richelieu and the British battleship HMS Barham. Barham was hit twice by secondary batteries and Richelieu was struck by two 15in shells, causing no serious damage. Richelieu was further damaged in the battle when a 380mm shell blew back and disabled two guns in the number 2 main turret, attributed to the use of the wrong type of propellant. The British force was beaten off.
Temporary repairs were completed by 24 April 1941 and Richelieu could sail on three engines at 14 knots (26km/h), but with only three usable main guns after another explosion in a 380mm mounting.