The Yongle Tongbao cash coins were notably not manufactured for the internal Chinese market where silver coinage and paper money would continue to dominate, but were in fact produced to help stimulate international trade as Chinese cash coins were used as a common form of currency throughout South, Southeast, and East Asia.
However, as these coins were primarily manufactured for foreign trade and to be carried by envoys of the Chinese court they generally did not circulate within China itself as silver coinage and banknotes would continue to remain the dominant media of exchange.
These coins with Ming dynasty inscriptions remained in circulation in Japan until they were officially prohibited by the Tokugawa shogunate in 1608.
[12] On the 5th month of the year Eiroku 3 (永禄三年, or 1560 in the Gregorian calendar), daimyō Oda Nobunaga was preparing for the Battle of Okehazama and while he had an army of forty thousand men, he could only gather around two and a half thousand soldiers for this decisive battle, Oda Nobunaga then went to pray for a victorious military campaign at the nearby Atsuta-jingū, he asked the Gods to show him a sign that his prayers would be answered and while looking at a handful of Eiraku Tsūhō cash coins decided to throw them in the air, when they fell back on the ground they all landed with heads up, he took this as a sign that the Gods would bless him and informed his men that they shall be victorious as they Gods favoured them.
[13] After Oda Nobunaga's forces were victorious his retainer Hayashi Hidesada said that the Gods must've really spoken through these coins to which Nobunaga replied by saying the Zen Buddhist proverb "I only know that I'm okay with what I got" (吾唯知足, ware tada taru o shiru) and presented to him an Eiraku Tsūhō coin of which both the obverse and reverse sides were heads.