Ryukyu Islands

The Ryukyu Islands, as seen on a map at the Pacific Aviation Museum at Pearl Harbor

• Other Names: 南西諸島 (nansei shotou)
• Japanese: 琉球諸島 (Ryuukyuu shotou) or 琉球列島 (Ryuukyuu rettou)

The Ryûkyû Islands are a chain of islands stretching from just south of Kyushu down to just before Taiwan, just to the west of the Kuroshio current which brings warm water from the south up to the Ryukyus, Japan, and Korea.

Historically independent, the islands were united under the Ryûkyû Kingdom in the 15th-16th centuries before the Satsuma han invasion of Ryûkyû in 1609. Those islands north of Okinawa Island were annexed by Satsuma at that time and remain part of Kagoshima prefecture today, while Okinawa and all those to the south remained under the control of the Ryûkyû Kingdom, and today comprise Okinawa prefecture.

Geography

The islands of the chain are considered in a number of groupings. Listed from north to south, they are:

• Satsunan Islands (Kagoshima pref.)
  • Ôsumi Islands - incl. Tanegashima, Yakushima, Kuchinoerabujima, Kuroshima, Takeshima, and Iô Torishima
  • Tokara Islands - incl. Kuchinoshima, Nakanoshima, Tairajima, Suwanosejima, Akusekijima, Gajashima, and Takarajima
  • Amami Islands - incl. Amami Ôshima, Kikaigashima, Tokunoshima, Okinoerabujima, and Yoronjima
• Okinawa Islands (Okinawa pref.) - incl. Okinawa Island, Izena Island, Iheya Island, Kumejima, Iejima, and the Kerama Islands
• Sakishima Islands (Okinawa pref.)
  • Miyako Islands - incl. Miyakojima, Ôgami Island, Ikema Island, Irabu Island, Shimoji Island, Kurima Island, Minna Island, and Tarama Island
  • Yaeyama Islands - incl. Ishigaki Island, Taketomi Island, Kohama Island, Kuroshima, Hatoma Island, Iriomote-jima, Hateruma Island, and Yonaguni Island

The fifty-five major islands in the chain constitute a total land area of 1,193 square miles, and are comprised of a series of seamounts, separate from the continental shelf, formed at the boundary of the Eurasian and Philippine Plates.

Unlike the Japanese Archipelago, which is volcanic, the islands of Ryûkyû formed from limestone coral, and so have a very different geology and topography. There are no serious mountains in the Ryukyus, and the average height above sea level across the entire archipelago is a tiny fraction of that of the far more mountainous islands of Japan and Taiwan.

History

Early History

The archaeological record shows that human habitation in the Ryukyus began roughly 20,000 to 30,000 years ago. More recent major waves of immigration, from a variety of directions, settled the northern Ryukyus around 9000 years ago, and the Sakishima Islands (the southern Ryukyus) around 4500 years ago.

The overall chain of islands continues relatively regularly from Kyushu to Taiwan, with one island, or small group of islands, after another, such that one can travel from one island to another without ever being out of sight of land (provided it's a clear day); however, there is a significant gap, 270 km wide, between Okinawa and the islands to the south, known as the Kerama Gap. As a result, while the people of Okinawa and the various islands north of it engaged in considerable trade with one another and with "mainland" Japan, the islanders of Sakishima remained disconnected from those interactions until around the 11th century CE.

The 10th-11th centuries saw considerable technological and commercial developments in Song Dynasty China (960-1279), along with various concurrent developments in Heian period Japan. Interactions between China, Japan, and the Ryukyus increased, and migrants between the three regions introduced the cultivation of rice, wheat, barley, and other crops, and the raising of livestock into the Ryukyus.

The people of the various islands, over the course of time, formed up into complex societies, generally taking the form of chiefdoms.

Age of Maritime Trade

By the beginning of the 14th century, the various chiefs of areas of Okinawa Island were unified under a single head chieftain, sometimes today retroactively called a "king." However, in the 1310s, the headchieftain Eiji was succeeded by his son Tamagusuku who, whether for lack of personal charisma or leadership ability, or for some other reason, failed to command the loyalty of the other chieftains. The island of Okinawa thus came to be divided into three chiefdoms, or kingdoms, known as Hokuzan, Chûzan, and Nanzan. This period of division is known as the Sanzan period.

Chûzan entered into tributary relations with Ming Dynasty China in 1372, with the other two doing the same within the ensuing several years. Chûzan quickly grew more wealthy and more powerful than the other two, conquering them and uniting the island of Okinawa under its control by 1429.

Over the rest of the 15th and 16th centuries, the Ryûkyû Kingdom, as the Okinawan state might now be called, extended its influence to the north and to the south, making islands as far south as Yonaguni and Hateruma, and as far north as the Amamis its tributaries, or conquering them outright. The kingdom meanwhile engaged quite actively in overseas trade, becoming a crucial hub of maritime trade between Korea, Japan, China, and various polities of Southeast Asia.

References

• Richard Pearson, Ancient Ryukyu, University of Hawaii Press, 2013.