The by forces of the Japanese feudal domain of Satsuma took place from March to May of 1609, and marked the beginning of the Ryukyu Kingdom's status as a vassal state under the Satsuma domain. Former Satsuma territories that had been invaded by the Ryukyu Kingdom, such as the Amami Islands, were reintegrated into the Satsuma domain. The invasion force was met with stiff resistance from the Ryukyuan military 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 the Okinawa Prefecture.
Etymology The war was called the , with 1609 being a kiyū year in the sexagenary cycle. It was also called the by the Ryukyu Kingdom.Chūzan Seikan (), chapter 2: "" In Japan, the war was called the or the during the Edo period. pp.234
Background Satsuma's invasion of Ryukyu was the climax of a long tradition of relations between the kingdom and the Shimazu clan of Satsuma. The two regions had been engaged in trade for at least several centuries and possibly for far longer than that; in addition, Ryukyu at times had paid tribute to the Ashikaga shogunate (1336–1573) of Japan as it did to China since 1372.
In 1429, during the reign of King Shō Hashi, Ryukyu invaded Okinoerabu Island and Yoron Island. This was the first stage of Ryukyu's southward policy () out of Okinawa island. In 1447, King Shō Shitatsu conquered Amami Oshima. In 1466, King Shō Toku attacked Kikai Island on two occasions. The fierce resistance of the islanders resulted in many casualties, but the island was finally placed under the control of the Kingdom of Ryukyu. King Shō Toku himself led 2,000 soldiers in large-scale operations but the cost of the war became a cause of domestic discontent. The Amami Islands became part of the Ryukyu Kingdom's territory from the Muromachi period onwards, along with the other Nansei Islands.
The Amami Islands (Amami Oshima, Tokunoshima, Okinoerabu Island, Kikai Island, etc.) traded with the Dazaifu, as attested as "Aakumi Island" () in the Mokkan. During the Kamakura to Nanbokucho periods, Amami was under the Hojo Tokumune's property. Later Chikama-Shi () was reorganised as stewards (Jitō) of the Satsuma Province, a territory of Shimazu clan.
During this era, the Ryukyu kingdom expanded north and south and new territory provided a stable basis for trade in the kingdom thereafter.
In the final decades of the 16th century, the Shimazu clan, along with Toyotomi Hideyoshi, who ruled Japan from 1582 to 1598, requested or demanded various types of aid or service from the kingdom on a number of occasions. King Shō Nei (r. 1587–1620) met some of these demands. Shō Nei sent a tribute ship, the Aya-Bune, to Satsuma in February or March of 1592,No.851 pp.64 and agreed to provide approximately half of his allocated burden in preparation for the invasion of Korea in 1593. However, Shō Nei also ignored many communications from Shimazu and Hideyoshi, which spurred the Shimazu, with the permission of the newly established Tokugawa shogunate (1603–1867), to invade Ryukyu in 1609, claiming it to be a punitive mission.
One of the chief events which spurred Satsuma to aggression occurred when Hideyoshi launched the first of two invasions of Korea. In 1591, Shimazu Yoshihisa said that "Hideyoshi ordered Ryukyu and Satsuma to contribute 15,000 troops in order to invade China; however, Ryukyu is a far country and Japanese military strategy is unfamiliar to your forces. I exempt you from mobilization of the troops. In exchange, however, you must supply 10 months' rations for 7,000 troops.". China was the original target of the war. pp.60No.785 Sho Nei supplied only half of the demanded amount in 1593.
Following Hideyoshi's death in 1598, and Tokugawa Ieyasu's subsequent rise to power, Shō Nei was asked by Satsuma to formally submit to the new shogunate, a request which was ignored. In 1603, some Ryukyu sailors were cast ashore on the coast of the Sendai domain, and Tokugawa Ieyasu sent them back to Ryukyu.No.1119 The Shimazu asked Ryukyu to thank Ieyasu again, but Ryukyu ignored the request. The Shimazu then requested to launch a punitive mission against Ryukyu. Approximately 100 ships carrying roughly 3,000 soldiers concentrated at Yamakawa harbor on March 1, 1609. Ichirai Magobee, who was one of them, would write a diary documenting the expedition. The fleet left harbor on March 4, under the command of Kabayama Hisataka and Hirata Masumune.
Campaign
Amami Island The Satsuma fleet arrived at Amami Ōshima on April 7, where the Amamian people did not resist, but assisted the Satsuma army. Tameten (), the chief of Kasari, was a subject of Kabayama, and called on the Amamian people to surrender. Shigetedaru (), the chief of Yakiuchi, supplied the Satsuma army. On April 10, Shō Nei was informed of Satsuma's landing on Amami, and he sent Ibun (), the priest of Tenryu temple,Shō Taikyū constructed Tenryu-ji. No one knows its location. to Amami in order to surrender, but Ibun missed the Satsuma army for unknown reasons. On April 16, 13 Satsuma ships then left for Tokunoshima in advance, and the others left Amami at 6 am on April 20.
Tokuno Island On April 17, 13 ships arrived at Tokunoshima and dispersed. Two ships arrived at Kanaguma, but nothing happened. Eight ships arrived at Wanya.a harbor of Amagi town. The ships were besieged all night by 1,000 people. On April 18, Satsuma troops disembarked, fired into the crowds, and killed 50 people. Three ships arrived at Akitoku,present Kametoku harbor in Tokunoshima town. and were attacked at the water's edge by the Akitoku people. However, troops quickly fought back and killed 20–30 people. The Satsuma fleet also arrived at Akitoku at 4pm, April 20. On April 21, Kabayama left for Okierabu Island with 10 ships in advance. Others left Tokunoshima at 10am, April 24, and arrived at Okierabu at sunset. They met Kabayama and his ships there, and quickly departed for Okinawa Island.
Okinawa Island The Satsuma fleet arrived at Unten harbor on the Motobu Peninsula of Okinawa island on April 25 at 18:00. On April 27, some disembarked. They found Nakijin Castle deserted, and set fires in several places. As soon as Shō Nei heard of Satsuma's arrival at Nakijin, he called KikuinHe became Zen priest in early life, and went Japan to study Zen. 10 years later, he came back to Ryukyu, became the chief priest of Enkaku-ji. When Satsuma invaded, he was old and had retired from chief of the temple. After this war, Shō Nei constructed Seirai temple () for Kikuin. Sho Nei gave Kikuin the title of prince, and ordered him to succeed the prince regent Shō Ko. Kikuin assisted Sho Nei for several years, and then he retired again. He died October 13, 1620. No.69, the zen master, giving him a royal order: "You had lived in Satsuma for several years, so you know three lords of the Shimazu clanShimazu Yosihisa, Yoshihiro, Iehisa very well. Go and make a proposal for peace." Kikuin and his diplomatic mission, with Kian as an assistant, left the Ryukyuan royal capital, Shuri at 8am, April 26, and arrived at Kuraha. Currently a part of Onna village at 12pm. They left Kuraha for Onna by boat. On April 27, they left Onna, and arrived at Nakijin. Kikuin parleyed with Kabayama, who then ordered peace talks at Naha.
In the early morning of April 29, the Satsuma fleet and Kikuin left Unten harbor. They arrived at Ōwan, near Yomitanzan or (Ōwan Toguchi) downstream of the Hijya River at 6pm. The Ryukyuan Mission left immediately, and arrived at Makiminato at 10pm, where they left their boat, and arrived late at night. Kikuin reported Kabayama's order to Shō Nei, and went down to Naha in the early morning. At Ōwan, Kabayama sent some of his officers to Naha in order to fulfill his promise, while he disembarked his other men, because he heard that there was a chain at the entrance of Naha harbor. "If there is a chain, no ship can enter the harbor."No.553 Kabayama and his army then landed at Ōwan, and marched to Shuri.
At 2 PM, May 1, the Satsuma ships entered Naha harbor, and immediately held peace talks at Oyamise ().Satsuma delegation: . Ryukyu: "Kian diary" At that time, there was a fire in Shuri, and Kabayama's force reacted and surged forward. Some Satsuma officersIchirai-Oribe () and Murao-Syosu () with their troops. "Kian diary" ran up to Shuri from Naha, and calmed down troops. Because Shō Nei gave Kabayama his own brother Shō Ko,He was the regent of the Kingdom. He assisted his brother but died at 33 years old in Japan, on August 21, 1610. pp.201 and all three of his ministers as hostage, Kabayama ordered his men to return to Naha from Shuri, and all of the Satsuma army were there by 4pm, May 1. On May 4, Shō Nei left Shuri Castle, and on May 5, some Satsuma officers entered the castle, and started making an inventory of treasures they found there.
Aftermath
On May 17, Shō Nei departed Unten harbor for Satsuma along with roughly one hundred of his officials. In August, 1610, he met with the retired Shōgun Tokugawa Ieyasu in Sunpu Castle. He was then taken to Edo, for a formal audience with Shōgun Tokugawa Hidetada on August 28. On December 24, he arrived at Kagoshima, where he was forced to formally surrender and to declare a number of oaths to the Shimazu clan. In 1611, two years after the invasion, the king returned to his castle at Shuri. In the king's absence, Kabayama Hisataka and his deputy Honda Chikamasa governed the islands on behalf of their lord Shimazu Tadatsune. 14 samurai officials from Satsuma, along with 163 of their staff,Kerr, George H. (2000). Okinawa: the History of an Island People. (revised ed.) Boston: Tuttle Publishing. p159. examined the kingdom's political structures and economic productivity, and conducted land surveys of all the islands. Following the king's return to Shuri and the resumption of governance under the royal establishment, some Ryukyuan officials went to Kagoshima as hostages.
The surrender documents signed at Kagoshima in 1611 were accompanied by a series of oaths.These can be found in translation in Kerr. pp160-163. The king and his councilors were made to swear that "the islands of Riu Kiu have from ancient times been a feudal dependency of Satsuma",Smits, Gregory (1999). "Visions of Ryukyu: Identity and Ideology in Early-Modern Thought and Politics." Honolulu: University of Hawai'i Press. p16. and that there was a long-standing tradition of sending tribute and congratulatory missions on the succession of the Satsuma lords, though these were clearly not true. The oaths also included stipulations that the kingdom admit its culpability in ignoring and rejecting numerous requests for materials and for manpower, that the invasion was justified and deserved, and that the lord of Satsuma was merciful and kind in allowing the king and his officers to return home and to remain in power. Finally, the councilors were forced to swear their allegiance to the Shimazu over their king. Tei Dō, a royal councilor and commander of the kingdom's defense against the invasion, refused to sign the oaths, and was subsequently beheaded.