Invasion of Ryukyu

Map of Ryukyu Kingdom

Date	March–May 1609
Location	Ryukyu Islands
Result	Satsuma victory; Ryukyu becomes a vassal state

Belligerents

Ryūkyū Kingdom

Satsuma Domain of Japan

Commanders and leaders

Shō Nei
Tei Dō

Shimazu Tadatsune
Kabayama Hisataka
Hirata Masumune

Strength

Unknown

3,000 men in 100 ships

The invasion of Ryukyu (琉球侵攻, Ryūkyū Shinkō^?) by forces of the Japanese feudal domain of Satsuma took place in 1609, and marked the beginning of the Ryūkyū Kingdom's status as a vassal state under Satsuma. The invasion force was met with stiff resistance on all but one island during the campaign. Ryukyu would remain a vassal state under Satsuma, alongside its already long-established tributary relationship with China, until it was formally annexed by Japan in 1879 as Okinawa Prefecture.

The war is called Disturbance of Kiyū (己酉ノ乱, Kiyū no ran^?) (1609 being an kiyū (己酉) year in the sexagenary cycle) or Japanese Disturbance of Kiyū (己酉倭乱, Kiyū Wa ran^?) by Ryukyu Kingdom. In Japanese, the war was called Ryukyu Expansion (琉球征伐, Ryūkyū Seibatsu^?) or Ryūkyū iri (琉球入り, "entry into Ryukyu") during the Edo period, and was called Okinawa Expansion Campaign (征縄役, Sei Nawa no Eki^?) by many Japanese scholars before WWII.

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