Japan - Ei Raku Sen, Nobunaga era coin

See Hartill " Early Japanese Coins" ; p. 24 for the details and story involving the famous Nobunaga. These coins were exported from Ming dynasty China in great quantities during the 16th Century.
Oda Nobunaga (織田信長, 23 June 1534 – 21 June 1582) known as "Owari no Otsuke" (Fools of Owari), was a Japanese daimyo and one of the leading figures of the Sengoku period. He is regarded as the first "Great Unifier" of Japan. His action in war gave him the nickname of "Oni Daimyo" (Demon King). This was a very trusted and used coin in the Kanto regions, it is not specifically associated with Nobunaga exclusively, it was used during the 15th - 17th centuries. However, Hartill lists it as 'R' or rare.
Nobunaga was head of the very powerful Oda clan, and launched a war against other daimyos to unify Japan in the 1560s. Nobunaga emerged as the most powerful daimyo, overthrowing the nominally ruling shogun Ashikaga Yoshiaki and dissolving the Ashikaga Shogunate in 1573. He conquered most of Honshu island by 1580, and defeated the Ikkō-ikki rebels in the 1580s. Nobunaga's rule was noted for innovative military tactics, fostering of free trade, reforms of Japan's civil government, and the start of the Momoyama historical art period, but also for the brutal suppression of those who refused to cooperate or yield to his demands. Nobunaga was killed in the Honnō-ji Incident in 1582, when his retainer Akechi Mitsuhide ambushed him in Kyoto and forced him to commit seppuku. Nobunaga was succeeded by Toyotomi Hideyoshi, who along with Tokugawa Ieyasu completed his war of unification shortly afterwards. [Wikipedia]