Merchant flag of the Ryukyu Kingdom
<a href="//commons.wikimedia.org/wiki/User:Samhanin" title="User:Samhanin">Samhanin</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>, source: 琉球交易港図屏風, <a rel="nofollow" class="external text" href="http://himoji.kanagawa-u.ac.jp/publication/doc/Amami1.pdf">日本近世生活絵引 奄美・沖縄編</a>