Imperial Chinese missions to Ryukyu Kingdom

Imperial Chinese missions to the Ryūkyū Kingdom were diplomatic missions which were intermittently sent by the Yuan, Ming and Qing emperors to Shuri, Okinawa in the Ryūkyū Islands. These diplomatic contacts were within the Sinocentric system of bilateral and multinational relationships in East Asia.

Some missions were sent to perform investiture ceremonies for the King of Ryūkyū, formally acknowledging him as King on behalf of the Chinese Imperial Court, and as a tributary subordinate.

Shuri was the royal capital of the Ryūkyū Kingdom. It is today part of the city of Naha, Okinawa.

Upon the accession of a new king, the news was generally communicated to the Chinese capital, along with a petition for investiture, by a formal Ryukyuan tribute mission. Following the 1609 invasion of Ryukyu, beginning with the succession of Shō Hō, Satsuma Domain also had to be notified and asked for approval and confirmation of the new king.

Chinese envoys would then be dispatched - sometimes quite quickly, sometimes not until over a decade later - arriving in ships called ukwanshin (御冠船^?, lit. "Crown Ships") in Okinawan. The mission would usually consist of two official envoy ships, separate crafts carrying the chief envoy and his deputy, as some uncertainty accompanied the journey; these would be accompanied by a number of merchant ships. During Japan's Edo period, an agent from Satsuma known as a kansen bugyō (冠船奉行^?, "Investiture (Crown) Ships Magistrate") would be sent down to Ryūkyū to supervise the exchanges and interactions between Chinese and Ryukyuan officials, albeit from somewhat of a distance, given the policy of hiding Satsuma's involvement in Ryūkyū from the Chinese.

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