L’étude des chars B 1 débute dès le lendemain de la première guerre mondiale. Fruit de la première coopération industrielle il sera conçu en conservant les meilleurs éléments des prototypes présentés. Construits à 35 exemplaires, les B1 seront les premiers vrais chars de bataille de l’armée française. Leur mise au point sera longue et complexe et il faudra plus de dix ans entre la promulgation du programme et la construction en série. Char de transition, en attendant les B1 bis, le B1 connaîtra ses heures de gloires tragiques au printemps 1940. Certains exemplaires, à bout de souffle, prendront part aux combats de la campagne de France après avoir été modernisés.

The design of the B1 tanks started as soon as the Great War was finished. The result of the first industrial collaboration, it was designed by retaining the best elements of the prototypes that were presented. With 35 tanks made, the B1 was the French army's first battle tank. Their development was long and complex and it took ten years between the beginning of the program and the start of production. A transitional tank, whilst awaiting the B1 bis, the B1 saw service during the tragic days of the spring of 1940. Some of these tired old tanks took part in the fighting during the Battle of France after having been modified.