This comfort food is thought to have originated during the 100 Years' War, when the English laid siege to the town of Castelnaudary, and to feed their soldiers, the rationed locals grabbed whatever they could get their hands on to invigorate the combatants. In a large bowl, they simmered bacon, pork, beans and sausages, and, according to legend, the resulting meal gave the soldiers of Chaur enough strength to drive the invaders out of Occitania!
At least, that's what the great cassoulet brotherhood (founded in 1970) maintains, and it's true that the first written mention of the recipe appears in Taillevent's famous "Viandier" in the 14th century. There's no mention of whether the Cassole, the atypical container associated with cassoulet, was already in use, but 7 centuries later we find that the beans have been replaced by haricot beans. As far as meats are concerned, those from the South-West of France, such as confit de canard and saucisse de Toulouse, are still preferred.