plate on the faces. The main armored deck was thick, and the conning tower had thick sides. Service history Construction and escape to Casablanca The French Navy awarded the contract for Jean Bart on 27 May 1936 to the Chantiers de Penhoët shipyard in Saint-Nazaire, although construction was sub-contracted to the adjacent A. C. Loire shipyard as its own facilities were busy with the Dunkerque-class battleship . The keel for Jean Bart was laid down on 12 December, less than three weeks before the Washington Treaty expired. The construction of Jean Bart and her sister ship placed France in violation of the terms of the treaty, which had limited the country to build of battleships during the ten-year building moratorium. The two Richelieus and the two Dunkerque-class battleships totaled of battleship tonnage. France used the Anglo-German Naval Agreement, which Britain had unilaterally signed with Nazi Germany (and in the process effectively nullified the naval disarmament clauses of the Treaty of Versailles) in June 1935 to dismiss British objections to the new ships. Serious work on the ship was nevertheless delayed owing to the shortage of dockyard workers and the need to complete the hull of the Strasbourg so she could be launched later that month. The dry dock used to build the ship was A. C. Loire's newly completed Caquot dock, named for its designer, Albert Caquot, though it was commonly referred to as the "Jean Bart dock". Work on the ship initially proceeded slowly, though the increase in tensions with Germany in early 1939 leading to the German invasion of Poland and the outbreak of World War II led to greater emphasis being placed on completing the ship. She was launched on 6 March 1940, but following the initial German successes in the Battle of France in May, the builders realized that the normal process of fitting-out would have to be abandoned in favor of preparing the vessel to be moved from the port. Work on the ship's propulsion system was greatly accelerated: some 3,500 workers were assigned to the project, and in the span of a month, three of her boilers, two sets of turbines, two turbo generators, and two pumps had been installed, along with critical internal communications systems. The outer shaft screws were installed on 6 and 7 June, and her three aft boilers had fires lit for the first time from 12 to 14 June.