The French Army had been pursuing the replacement of the Canon de 155mm L Mle 1877de Bange gun since 1909. Spurred by the events in the Russo-Japanese war of 1904-5 it was realised that relying on an old gun which was almost immobile for long range artillery support wasn't a viable strategy. The French Army Artillery Technical Committee produced requirements for a de Bange replacement in November 1909. The requirements included two different guns with a range of 13 to 14 km with a maximum elevation of 35 to 40 degrees and a modern mobile carriage. It was suggested the requirement could be met by modification of existing equipment. The 1909 requirement was replaced by a February 1913 one created by a committee headed by General Lamothe. The requirements included a longer range of 17 to 18 km, a calibre of 130 to 140mm and the gun was to be transportable in two loads. However, little was done before the outbreak of WW1. After the outbreak of war about 120 Canon de 155mm L Mle 1877/1914 Schneider guns which used the 155mm de Bange barrel were ordered. In order to address the French Army's deficit of long rangeheavy artillery the obvious conversion of suitable calibre Naval guns to land use was undertaken. There were surplus Canon de 138 mm Modèle 1891 guns which had been the secondary batteries of pre-dreadnaught battleships. The in serviceCanon de 138 mm Modèle 1910 was also converted to land use. Both FAMH and Schneider produced land carriages in early 1916 and mid 1917 respectively. Although these guns generally met the range requirements of the French Army the carriages were heavy, clumsy and slow firing. Saint-Chamond also constructed 12 Canon de 145mm Mle 1910 sur affût Saint-Chamond in 1916 using bored out 14 cm Mle 1910 L/55 barrels. The final adaptation of the 14 cm Naval gun to land use was the Canon de 145 L Mle 1916 Saint-Chamond where new, slightly shorter, barrels were constructed by the Fonderie de Ruelle and mounted on a Saint-Chamond carriage. The barrels were delivered in 145mm calibre with an option to bore them out to 155mm when they wore out although this wasn't done during WW1. The box trial was fairly conventional except for a pair of semi-circular plates at the front of the carriage. Because the gun used the cradle, recoil and recuperators of the Naval gun there was some residual recoil which was not absorbed by the carriage. The practice was to place a pair of inclined ramps under the circular plates so the gun could ride up on these during firing and slide back down into battery. The gun was normally moved as a single unit towed by a 4-wheel drive heavy truck with auxiliary wheels under the end of the trail. It was found the 145mm Saint-Chamond gun was very accurate with very little dispersal of shots. 200 barrels from Ruelle and 160 carriages from Saint-Chamond were ordered in 1916 and the gun entered service in April 1917. This gun along with the Canon de 155mm GPF made up the equipment of the RALTs which made the heavy French artillery so effective at the end of the war. The 145mm guns were converted to 155mm in the 1920s and served in heavy artillery regiments until WW2. After the fall of France in 1940, it is estimated 210-215 guns were captured by the Germans. In German service they were known as the 14.5 cm Kanone 405 or 14.5 cm K 405 and employed in Atlantic Wall defenses in German occupied Western Europe.
