Although cultural commonalties clearly indicate that Ryukyu and Japan have been part of the same civilisation since ancient times, geographical factors served to keep the regions apart for a long period. Formal economic and political relations were established in the early 15^th century. And whilst Japan’s initial claim of sovereignty over the islands can be traced to the same period, no action was taken to make this manifest for another two centuries. The principal reason for this, as previously mentioned, was that Japan had fallen into a state of political disorganisation. Almost a century-and-a-half of relative stability was created with the establishment of the Muromachi Shogunate in Kyoto in 1336, though political in-fighting and economic problems were constants during the period. Many regional warlords who had been pivotal on the battlefield in the fall of the Kamakura Shogunate did not receive rewards they felt appropriate and proceeded to take unilateral action to redress this state of affairs. Simmering frustrations led ultimately to the outbreak of the Onin War and the fall of Muromachi, in 1467. After that, and until the late-16th century, there was virtual chaos. Political power tended to reside with whichever warlord happened to have control over the strongest military. The Imperial Family had undergone so many transformations via intermarriage with politically influential factions that it no longer had any credibility.[1]

Ryukyu vessels first began conducting trade missions to Korea and Japan from the late-14^th into 15^th century. At times ships bypassed Japan on voyages to Korea, but more often ported at Kagoshima or Hakata in Kyushu, from there following Japan’s Inland Sea to Sakai en route to Kyoto.[2] Gifts were given when ties were established and on subsequent trips. Most important, is that at the start of the 15^th century neither Japan nor Satsuma were claiming ownership of Ryukyu. There are records of the Muromachi Shogun, Ashikaga Yoshimochi, sending a letter to King Sho Shisho in 1416 addressing him as Ryukyu koku no yo no nushi, or 'Master of the Country of Ryukyu.'[3] While choosing the Japanese literation Ryukyu rather than the Chinese word Liuqiu, references to a 'Country of Ryukyu' were identical with Ming records. Both countries recognised Ryukyu koku as a distinct political community.

A shift occurred in the mid-15^th century. While Japan had a capital and head of state, real powers had long dispersed into the regions, seized by the daimyo, or feudal lords. The daimyo operated their own economies, including foreign trade or piracy, and felt no obligation to support Kyoto. Shimazu of Satsuma, one of the more powerful daimyo, had the wisdom to formalise trade with Korea's Li Dynasty in 1395, sending 120 missions from then to 1504.[4] Kagoshima was already a port of call for Ryukyuan ships and Shimazu saw that this could work to further advantage. Ryukyu vessels arrived with exotic wares that were in short supply in the Japan-Korea region and were keen to develop these markets. The main threat was rampant piracy in the area. Recognising this, Shimazu entered into a profitable arrangement by offering Kagoshima as marketplace for goods from Naha and agreeing to bodyguard Ryukyu vessels. Shogun Ashikaga Yoshinori was aware of these developments and, therefore, eager to establish good relations with Shimazu. If little else, he could still award tokens of power or legitimacy. On a whim, in 1441, Yoshinori  conferred rights of jurisdiction over Ryukyu to Shimazu Tadakuni of Satsuma.[5] Although Shuri was oblivious to this transfer of sovereignty, and while it had no legal credibility, Shimazu became more paternalistic. This worsened after Shimazu received shogunal authority to monitor Ryukyu ships and trade in 1471 and 1480.[6] Shuri appears to have taken a pragmatic approach to these irritations in order to maintain a quiet existence, but must, at some point, have realised that something was decidedly awry.[7]

Oda Nobunaga installed Ashikaga Yoshiaki as a puppet Shogun in 1568, and by his death in 1582 had militarily wiped out or tamed the daimyo, bringing Japan to the verge of peace and political unification. The task was completed by Toyotomi Hideyoshi. Such was the swiftness of the process that by the closing decade of the 16^th century Hideyoshi had set his sights on expansion into Korea and China. In 1590, Shimazu Yoshihisa was told that Ryukyu would be required to contribute troops and provisions toward the invasion of Korea. Shimazu, knowing this would be tricky, asked that Shuri's obligation be to provide only supplies.[8] With consent Shimazu forwarded a letter to King Sho Nei in 1591, asking that a 10-month supply of provisions for 7,000 men be delivered to Bonotsu in early-1592.[9] Sho Nei, anxious not to become embroiled, ignored the demand. Caught between the Shogun's demands and Sho Nei’s refusals, Shimazu dispatched agents to Naha who were told Ryukyu was too poor to fulfil such requirements since foreign trade had been curtailed. A token shipment was sent in 1593, but by then the invasion had failed. Shuri sent word to China requesting assistance and warning of Japan's desire for territorial expansion into Asia. 

Shuri's sense of impending doom proved warranted. Upon Hideyoshi’s death a power struggle erupted between factions loyal to him and to Tokugawa Ieyasu, culminating in the Battle of Sekigahara in 1600. In 1603, Tokugawa emerged triumphant and established the Edo or Tokugawa Shogunate. Shimazu Yoshihiro of Satsuma had sided against Tokugawa in battle and was immediately stripped of title but his successors were treated leniently, if with caution. His successor, Shimazu Iehisa, visited Edo to pay his respects the new Shogun and advised Ryukyu King Sho Nei to do likewise. As usual, perhaps unaware of the magnitude of political change in Japan, Shuri refused. On previous occasions Shimazu might have made excuses, but his was now a more difficult position within the new order. Shimazu asked Ieyasu's consent to deploy a punitive task force to the islands and in February 1609, General Kabayama set sail from Kagoshima with 3,000 men in 100 vessels.[10] There were minor skirmishes en route, but Ryukyu posed little resistance. On 5^th April, Sho Nei surrendered Shuri and was transported with senior officials to Kagoshima to be, as Kerr notes, paraded as the first "foreign monarch" to submit to Japanese authority.[11]

Throughout 1610, Satsuma bugyo, or magistrates, with a staff of 168, began surveying (kenchi) all islands of the Ryukyus to assess their koku value.[12] In 1611, all islands north of and including Amami were incorporated into the Satsuma fiefdom and were therefore not included in the final koku valuation of Ryukyu. In September, Sho Nei was told that he could return to his kingdom provided he put his signature to a pledge (meiyakusho) known as the 'King's Oath:' the gist being that the present situation had been brought upon the kingdom by Sho Nei's disrespect for the Shogun. He had to agree that it was now only because of Shimazu’s generosity that he could resume his duties. Most importantly, he had to concur with the ludicrous statement that "the islands of Ryukyu have from ancient times been a feudal dependency of Satsuma."[13] Senior Ofu ministers, including the Sessei and Sanshikan, were similarly told to recognise Satsuma authority from ancient times and pledge loyalty. Shimazu dispatched a head-monitoring official, or zaiban bugyo and staff to reside in Naha and demanded that a Ryukyu minister of Sanshikan rank, called zaiban ufuyaku (oyakata) be resident in Kagoshima. As Sakihara points out, Ryukyu were thereafter listed in the official writ of stipend granted to Satsuma by the Tokugawa Shogunate.[14]

Myth and Reality in Satsuma-Ryukyu Relations

Shimazu’s conquest had been conducted as a demonstration of loyalty to the new Shogun, but his need to secure control over a vital source of revenue was a more pressing concern. The Shogun had not confiscated all Satsuma lands,[15] but had reduced the size of the domain and imposed a higher level of taxation. Clearly, Shimazu had to tighten up his financial affairs. He demanded no less of the Ryukyu King and Ofu. Whilst taking complete control of all aspects of China trade, Shimazu Iehisa's 'Fifteen Article Ordinance' (okite jugojo) banned the practice of financial awards to mistresses or on the basis of family origins, stressing that rewards should only be given in recognition of public service.[16] The King was instructed to keep temple and shrine construction within reasonable limits. Shimazu was aware of the relative decline in the kingdom's economy since exit from Southeast Asia and was not insensitive to the situation. Yet Shuri was still involved in tributary trade with China lucrative enough for Shimazu to make every effort to avoid interruptions. At the same time, to obtain maximum benefit from this trade he would have to ensure Shuri not fritter away more than necessary and that it learn to administer resources more efficiently. Although there are many recorded lapses, this new period under Satsuma is marked by a high degree of skill in resource management and efficiency in agricultural productivity and government organisation. The Ofu bureaucracy would come to play a far more visible role in the agrarian communities.

Though there developed a good deal of complexity to the system in later years, Shuri was obliged to pay taxes and tributes to Satsuma and lose control over trade with China.[17] Tribute tax was derived from the assessed productive capacity of all Ryukyuan lands. In 1611, on completion of surveys, Satsuma agents set the rice koku value of the Ryukyus at 89,086, of which some 50,000 koku (56% of the total) was assessed as royal family income.[18] Of the tax system in mainland Japan there was a correlation between population size and koku valuations. Since historians agree that the population figure at the start of the 17^th century was around 100,000, Satsuma's valuation can be seen as consistent with mainland levying standards, and as reasonably lenient. From the total koku value assessment, Shimazu received an annual payment of 8,783 koku,[19] about an eighth of which was in textiles rather than rice. The assessed tax figure for Shimazu was actually 11,933 koku, but transportation costs to Kagoshima for which Shuri was liable had to be factored in.[20] In addition, a personal tribute from the King's coffers was requested which was as much as 8,000 koku again. The largest amount of revenue coming from Ryukyu, however, was Shimazu’s share of Ryukyu-China trade, estimated at as much as 100,000 koku per year.[21] To put this in context, the total annual revenue of the Satsuma domain at the time stood at about 700,000 koku.[22] As such, income from Ryukyu accounted for 17% of Satsuma's total income during the early- to mid-17^th century.

It is common practice to attack the 270-year period of Satsuma rule, isolating it as Japan's first taste of colonial exploitation. The prevalent tendency is to link this with postwar debates on US bases in Okinawa and the Government of Japan's (GOJ) complicity with a Japan-US security alliance system that maintains them. However, there are significant problems with the argument. On the one hand, and in terms of the way we have come to define the concept, this certainly was colonialism with all attached negativity. The kingdom was taken, looted, and fell under the absolute authority of Shimazu who imposed taxes and held the threat of punishment for failure to comply with directives like a blade to the throat. On the other, and in terms of the political situation of the day, it was more complex. One must balance associated inflammatory words like conquest, exploitation, and tyranny: which pop up time and time again in discussions about this period, against the degree to which the new system suited Ryukyu within a rapidly changing geopolitical and geoeconomic environment and in terms of its internal modernisation requirements.[23] Proponents of what may be called 'exploitation continuity theories' generally avoid such historical grey matter and consequently contemporary debate suffers. Ryukyu sat in a vulnerable location at a time when China could not offer vassals protection, itself under threat from European powers acquiring territories in the Asian region apace.[24] Colonialism was on the rise throughout Asia in the 17^th and 18^th centuries.

Another argument holds that Shimazu was tyrannous, with his tax demands in particular leading to wide scale poverty and exploitation of the people. In truth, these demands were not as heavy as legend has it during the first two centuries of Satsuma rule and, perhaps most importantly, were quite egalitarian. The tribute tax, which fell mainly on agrarian households, was difficult to achieve if a harvest was poor. Yet while the figure was about 15% of assessed productivity in 1611, the real term figure was much higher after the introduction and improved production of high value crops like imo and sugar cane in the 17^th century, and with the opening of more land for cultivation.[25] The imo became a staple food item throughout Ryukyu, while sugar the main item for export to Japan. Droughts, famines, and violent typhoons were common, but the average household dealt with these as ever, being prosperous neither before nor after the Satsuma conquest. Those located at the bottom rung of the social hierarchy started at zero, but progressed to zero. In this sense poverty was relative. If anything, the field was levelled. Those high in the social hierarchy felt the pinch, losing relatively more. Arguably, this was a positive development of Satsuma rule. Only extreme monarchists can work from the proper philosophical foundation to legitimately vilify the Lord of Satsuma. He took most from the Ofu and social elite who were the biggest consumers and who had been, and continued to be, guilty of squeezing whatever they could from agrarian households. For the benefit of the latter Satsuma introduced better systems of food production and resource management.[26]

Furthermore, all of Japan was afflicted by this early-19^th century crisis which, in part, led to the fall of the Tokugawa. While siphoning trade profits and collecting taxes Shimazu did not escape obligation-free. Flexibility had to be shown in times of economic hardship and actual financial assistance to Shuri was necessary when a Chinese cefeng mission was due in port. The Chinese Emperor's tianshi, or 'celestial envoy,' would arrive with a retinue of at least 300 people, expecting lavish treatment and accommodation for the duration of their stay. This was the price for Shimazu had to pay to keep China-Ryukyu relations plodding along happily.[27] This became of greater importance after the new shogun Tokugawa Iemitsu prohibited all foreign intercourse, except that with China and Holland via Dejima Port in Nagasaki. This official sakoku, or exclusion policy, remained in effect for more than two centuries.