Analysis of information sources in references of the Wikipedia article "Jeu d'argent" in French language version.
« Many Japanese are naturally prone to gambling; in the old Kyoto court the vice was rife, and in the fourteenth and fifteenth centuries samurai would often stake their arms, armour, and horse trappings on a cast of the dice, even on the eve of a battle, and so have to go into action in incomplete panoplies, and sometimes with no armour at all. In Tokugawa times the vice did not reach this extent among the samurai, but it became common in Yedo and continued to be so throughout the history of the city. »