This article examines Governor Onaga’s remarks on the Ryukyu Kingdom and China’s tributary system by tracing the historical reality of sulfur supply, Ming military power, the Satsuma invasion of Ryukyu, and the transition from Ming to Qing rule. It reveals that the substance of the tributary system differed fundamentally between the Ming and Qing dynasties and exposes serious misconceptions in modern interpretations of Okinawan history.

February 24, 2017
What follows is a continuation of the previous chapter.
Governor Takeshi Onaga, moved by the fact that he was able to meet Premier Li Keqiang, spoke words of emotion and stated, “Okinawa once flourished as the Ryukyu Kingdom through exchanges with China and many other Asian nations. With China we maintained a tributary relationship,” thus referring to the tributary system.
Here, Governor Onaga exposed his inability to correctly understand Okinawan history.
The crucial historical fact is why the Ming dynasty sought to impose the tributary system upon the Ryukyu Kingdom in the first place.
Black gunpowder is counted as one of the three great inventions of the Han Chinese.
The raw materials for this black gunpowder were charcoal, saltpeter, and sulfur.
The mixing ratio was roughly 10–20 percent charcoal, 60–70 percent saltpeter, with sulfur comprising about the same proportion as charcoal.
Gunpowder was invented in Han Chinese regions because saltpeter was produced there in abundance.
However, sulfur production was scarce, and the Ming dynasty needed to obtain supplies from within the territorial domain of the Ryukyu Kingdom.
In response to Toyotomi Hideyoshi’s military campaign in Korea (the Imjin War), the Ming, as the suzerain power, provided military assistance, and at that time the main weapons were cannons.
Hideyoshi’s forces were armed with matchlock guns, and the amount of gunpowder they consumed differed greatly.
One reason Hideyoshi’s domination of the Korean Peninsula did not succeed was that he was inferior to the Ming in the volume of gunpowder used.
Shimazu Iehisa of Satsuma, having realized that Ming gunpowder production depended on the volcanic islands at Japan’s southern tip of Kyushu, obtained Tokugawa Ieyasu’s permission and dispatched the Satsuma warrior forces to Okinawa.
At that time, the five Amami Islands were ceded, and the territory north of Yoron Island was separated from the Ryukyu Kingdom and placed under the direct control of the Shimazu clan.
In this way, sulfur-producing regions were detached from the Ryukyu Kingdom.
Although the Ming had been able to thwart Hideyoshi’s ambitions largely thanks to sulfur tributes from the Ryukyu Kingdom, once the volcanic islands that supplied sulfur for gunpowder manufacture came under Shimazu control, Ming military power declined, and eventually the Ming dynasty collapsed, giving rise to the Qing dynasty, which placed the Han Chinese under its rule.
The Qing, having no need for sulfur-producing Ryukyu, initially showed no interest in it, but by order of the Satsuma Domain, Ryukyu was made to enter the Qing tributary system.
What the Satsuma Domain desired were Chinese goods such as silk and medicinal materials.
This time, the Satsuma Domain arranged the goods required by the Qing and conducted imports and exports via Ryukyu.
This was what came to be known as “tribute trade.”
Because the goods demanded by the Qing were not produced in Ryukyu, the kingdom carried out trade under the instructions of the Satsuma Domain.
As a result, the influence of the Satsuma Domain over Ryukyu became decisive, and in effect, Ryukyu drifted away from the Qing tributary system and became increasingly Japanized.
By the end of the Edo period, this was sufficient for foreigners who visited Ryukyu to recognize it as part of Japan.
These circumstances are detailed in the article by Keiryūnosuke published in last November’s issue of this magazine, titled “Perry Documents Excavation Scoop!”
In practical terms, Ryukyu had fallen out of the tributary system because it no longer possessed goods desired by the Qing.
Therefore, although both the Ming and the Qing employed the term “tributary system,” the contents were fundamentally different.
The Ming sought tribute directly from the Ryukyu Kingdom, whereas in the case of the Qing, Ryukyu entered the system at the direction of the Satsuma Domain.
It is from this perspective that Governor Onaga’s next statement becomes a matter of grave concern.