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 and coral islands, 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.

Traditionally, regions of the Ryukyus were referred to by poetic placenames using the word for "mountain" (san or zan). Prior to the unification of the island, Okinawa itself was divided into Hokuzan, Chûzan, and Nanzan. The distant Miyako and Ishigaki Islands were referred to as Taiheizan 太平山, Iheya and Izena, just west of Okinawa, were referred to as Yôhekizan 葉壁山, and the Kerama Islands were called Bashizan 馬歯山.

History

Early History

The archaeological record shows that human habitation in the Ryukyus began roughly 20,000 to 30,000 years ago. No archaeological remains have been found for the period from roughly 16,000 and 7000 BCE. Beginning around 7000 BCE, however, more recent major waves of immigration began to enter the Northern and Central Ryukyus from the north (Kyushu), and beginning around 2900 BCE, entering the Sakishima Islands from the south.

Agriculture is not believed to have begun in the islands until around 800 CE, with islanders previously subsisting in hunter-gatherer communities. Ironworking, meanwhile, is believed to have been introduced to the Amami Islands around 500 CE, and to have spread to the other Ryukyus from there.

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. Though the original inhabitants of the islands may have been more purely of an ethnic stock similar to that of the Ainu or the Jômon people, from at least the late first millennium CE, if not earlier, Okinawans began to more closely resemble mainland Japanese (Yamato people), an indication of considerable exchange and interaction between Japan and the Ryukyus and, perhaps, a significant number of migrants from Japan settling in the Ryukyus.

The people of the various islands, over the course of time, formed up into complex societies, generally taking the form of chiefdoms. This took place on Okinawa beginning around 1050 CE, and was accompanied by changes in patterns of subsistence and agriculture. Then, beginning around 1200-1250 CE, up until the 1420s, the island became embroiled in considerable violence, as local elites built fortresses called gusuku and fought one another for land and power. Trade activity also expanded considerably at this time. Archaeologist Richard Pearson identifies these two periods (c. 1050-1250, and c. 1250-1429) as the "Early" and "Late Gusuku Periods," while many other scholars simply lump the two together as the Gusuku period of Okinawan history. This is also the period when the Ryûkyû Islands begin to appear in foreign sources (mainly Chinese ones, such as the Ming shi-lu).

Gusuku construction and the associated rapid social and economic changes began first in the Early Gusuku Period in the Amamis, which were up until then the economic center of the Ryûkyû chain. Gusuku sites on Kikaigashima and the kamuiyaki pottery kiln sites on Tokunoshima are of particular significance. In the Late Gusuku Period, the economic center of the archipelago shifted to Okinawa Island, where it would remain down to the present time. Major gusuku on Okinawa include those at Urasoe, Nakijin, Katsuren, Nakagusuku, and Ôzato, with Shuri castle gaining in significance later in the period.

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.