Chikudun Pechin

Yukatchu (良人) were the aristocracy of the Ryukyu Kingdom; the scholar-bureaucrats of classical Chinese studies living in Kumemura, they held the majority of government positions.

The Yukatchu were part of a complex caste system that existed in Ryukyu for centuries. They were the feudal scholar-officials class that was charged with enforcing the law and providing military defense to the nation, Ryukyu Kingdom. The specific rank of a Yukatchu was noted by the color of his hat.

Ryukyuan Caste System:

The Yukatchu class was also responsible for the development of and training in the traditional fighting style, called Ti (Te), which developed into modern-day Karate. The Ryukyuan Yukatchu kept their fighting techniques secret, usually passing down the most devastating fighting forms to only one member of the family per generation, usually the eldest son.

The first time that the Yukatchu's weapons were confiscated was during the reign of King Shō Shin (1477–1526), who centralized the Ryukyu Kingdom by forcing the Aji to leave their respective Magiri and move to Shuri. He confiscated weapons from commoners and Yukatchu who weren't part of the Ryukyuan military to lower the possibility of rebellion. The second time that the Yukatchu were disarmed was after the invasion of 1609 by Satsuma Domain, which prohibited the carrying of weapons by the Yukatchu.

The Yukatchu were not completely without weapons however. Historians in Okinawa have recovered documents that state that Satsuma outlawed the ownership and sale of firearms in Okinawa, but the Yukatchu class and above were allowed to keep firearms that were already in their family's possession.

Toshihiro Oshiro, historian and Okinawan martial arts master, states:

There is further documentation that in 1613 the Satsuma issued permits for the Ryukyu Samure to travel with their personal swords (tachi and wakizashi) to the smiths and polishers in Kagushima, Japan for maintenance and repair. From the issuance of these permits, it is logical to infer that there were restrictions on the Ryukyu Samure carrying their weapons in public, but it is also clear evidence that these weapons were not confiscated by the Satsuma.

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Wikipedia