Kume Island was under the rule of Ryūkyū. The Kagoshima Japanese form of Ryūkyū is Jiki. As Ryūkyū's suzerain, Satsuma Domain had heavy financial reliance on brown sugar production in Amami and Ryūkyū. For this reason, Jiki metonymically refers to black sugar in Kagoshima Prefecture. The Okinawans found derogatory nuances in the word Jiki-jin (literally, Ryūkyū person/people, i.e., Okinawan people). Ryukyu Kingdom was replaced with Okinawa Prefecture in 1879. In the view point of Okinawans, Ryūkyū is an entity that no longer exists and accordingly there is no such group called "Ryukyuan people" today. The Ryukyu Islands and the Western origin of the concept The Kitab al-Fawa'id fi Usul 'Ilm al-Bahr wa 'l-Qawa'id (circa 1490) by the Arab navigator Ahmad ibn Mājid is the first known source outside the Sinosphere that mentions Ryūkyū. According to the Arabic book, Likīwū was a Jawi name for an island called al-Ghūr (الغور). Its association with iron, iron blades, and an antagonism toward China points to mainland Japan, rather than to Okinawa Island, however. In the Minhaj al-Fahir, Ibn Majid's student Sulayman al-Mahri made a similar reference to jazīrat Likyū (literally, Ryūkyū Island) as an alias of al-Ghūr. The Arabic term al-Ghūr appears to point to Chinese Luoji (落漈), an imaginary area in the sea east of China. The Chinese believed that sea water fell at Luoji and thereby that the sea level was kept constant despite the endless flow of river water into the sea. In Chinese narratives, Luoji was associated with Ryūkyū and the sea route to Okinawa Island. Through contact with Muslim merchants, the Portuguese learned that people called Gores visited Southeast Asian ports for trade. The first known Western reference to Gores was from Malacca in 1510, a year before the conquest of the port city by Afonso de Albuquerque. The Portuguese demonym apparently derived from Arabic al-Ghūr. In few years, Gores came to be associated with another name, Lequios or Lequeos. The Commentarios do Grande Affonso d'Alboquerque (1557) used a rare derived form Lequea as the name of their country. Early Portuguese sources were consistent with the Chinese view in that they considered the land of the Lequeos to be an island (ilha, singular). The Suma Oriental (circa 1515) by Tomé Pires was a prime example of this perception. After Fernão Pires de Andrade's expedition to Ming China from 1517 to 1518, Ryūkyū came to be described as islands