Ryukyuan mon

The Ryukyuan mon (琉球文, Ryūkyū mon, Okinawan: Ruuchuu mun) was the currency used in the Ryukyu Islands. The Ryukyuan monetary system was based on that of China, like those of many nations in the Sinosphere, with the mon (文) serving as the basic unit, just as with the Japanese mon, Vietnamese văn, and Korean mun. Like Japan had also done for centuries, the Ryukyuans often made use of the already-existing Chinese cash coins when physical currency was needed.

In the 14th and 15th centuries, the Kingdoms of Chūzan and Ryukyu produced their own coinage, but eventually transitioned back to Japanese mon and Chinese wén. Regardless of their origin, mon coins remained the de facto currency in the Ryukyu Kingdom throughout history up until 1879, when the kingdom was fully annexed by the Empire of Japan and the currency was officially replaced by the Japanese yen. Even after the introduction of the yen, however, mon coins continued to circulate within Okinawa Prefecture well into the 1880s, as the Ryukyuans were initially unwilling to use Japanese yen coins.

A second category of mon coins associated with the Ryukyu Kingdom are those bearing the name Ryūkyū Tsūhō (琉球通寳 "Ryukyu Currency"), which were minted by the Satsuma Domain, but were never actually used as regular currency in the Ryukyu Kingdom or Okinawa Prefecture. Instead, they were used as alternatives to the Japanese Tenpō Tsūhō coin and intended to bolster Satsuma's economy with additional coinage.