Place names are living witnesses to history. In Ming Dynasty (1368-1644) literature, Diaoyu Dao, otherwise known as Diaoyu Tai, was more frequently referred to as Diaoyu Yu. Yu means islet, a synonym to dao, island. Documents of Ming and Qing (1644-1911) dynasties on the Diaoyu Dao and its affiliated islands provide the earliest and most important historical evidence that Diaoyu Dao has been an inherent territory of China since ancient times. An investigation into the documents will highlight the fact that Diaoyu Dao has been part of China since the Ming Dynasty. It will also illustrate how China's maritime boundary in the East China Sea was established.

While the Japanese Government asserts Diaoyu Dao was terra nullius, the truth is that the uninhabited island does have an owner. With a clear analysis of historical facts, we will be able to set the record right and come up with a strong counterargument to Japan's claims that it "discovered" Diaoyu Dao and acquired sovereignty over it through "occupation."

The Chinese were the first to discover, name and exploit Diaoyu Dao

Residents in China's coastal areas have been exploring the sea for thousands of years. The ancient boat unearthed from the Kuahuqiao Ruins in Xiaoshan, Zhejiang Province, shows Chinese ancestors began navigating the East China Sea 8,000 years ago. Navigation records, known as "sailors' secret books" and later as "compass books," were passed down from generation to generation. The earliest such records that have survived to this day date back to the Ming Dynasty.

It is generally believed that the first historical record of Diaoyu Dao and its affiliated islands can be found in the book Voyage With a Tail Wind (Shun Feng Xiang Song) written in 1403. But we should trace the record earlier than that to The Compass Book of 36 Clans (San Shi Liu Xing Suo Chuan Zhen Ben).

Hong Kong scholar Chen Jia-rong pointed out in an article in the New Vision for Chinese Studies (Guo Xue Xin Shi Ye) quarterly that San Shi Liu Xing Suo Chuan Zhen Ben was found in A General Guide (Zhi Nan Guang Yi), a navigation book complied in 1708 by Cheng Shunze (Tei Junsoku), a noted scholar from Ryukyu, and kept in the library of the University of the Ryukyus. In a chapter titled A Record of Compass Routes, 14 routes from two sources were recorded: (1) Four were attributed to Title-Conferring Boat's Compass Book (Feng Zhou Zhen Bu), three of which mentioned Diaoyu Tai. The document said these routes were attributed to The Use of the Compass in Ocean Navigation (Hang Hai Zhen Fa) compiled by a title-conferring delegation sent by the Qing Dynasty to Ryukyu in 1683, which could be further traced back to the navigation records of Ming Dynasty explorer Zheng He in 1403. (2) Ten routes were attributed to San Shi Liu Xing Suo Chuan Zhen Ben, four of which mentioned Diaoyu Tai: Ryukyu to Fuzhou, Fuzhou back to Ryukyu, setting sail from Dongyongshan and setting sail from Diaoyu Tai.

San Shi Liu Xing Suo Chuan Zhen Ben is a collection of navigation records of the 36 clans. But when were the 36 clans dated? Collected Statutes of the Ming Dynasty (Ming Hui Dian) contains clear records that Emperor Taizu of the Ming Dynasty sent 36 clans from Fujian to Ryukyu in 1392, the 25th year of the Hongwu reign. "In the 25th year, King Zhongshan of Ryukyu sent his sons and nephews to the Imperial Academy," the book said. "Since Ryukyu paid tribute to the court, the emperor bestowed on it 36 clans who excelled at seafaring." Based on these records, we have reason to change the date of the earliest record of Diaoyu Dao in Ming Dynasty literature from the previously believed 1403, the first year of the Yongle reign, to the even earlier Hongwu reign (1368-98).

The discovery of San Shi Liu Xing Suo Chuan Zhen Ben was significant because such navigation records have a time-honored history. The Ming emperor sent the 36 clans to Ryukyu in the 1390s, which is the latest estimated date of the book. We may presume its earliest possible date based on the time when the phrase "compass route" came into use. The compass, one of the four great inventions of ancient China, was first used in navigation by Chinese sailors in the Northern Song Dynasty (960-1127). Xu Jing documented the use of the compass in a fleet in An Illustrated Record of the Xuanhe Emissary to Korea (Xuan He Feng Shi Gao Li Tu Jing). "Compass routes" and "compass books" could date back to that period. In light of this analysis, Chinese sailors could have first discovered and named Diaoyu Dao and used it as a navigational marker in the 11th-12th century at the earliest; or the 1370s at the latest, given records on the Ming Dynasty's dispatch of envoys to Ryukyu and the Ming Navy's patrols near the "Ryukyu Ocean" in the early Hongwu reign.

The compass book is an important piece of historical evidence that the Chinese were the first to discover, name and use Diaoyu Dao. China discovered the island at least 500 years before Koga Tatsushiro, a Japanese man, claimed to have "discovered" the island in 1884.

China first established sovereignty over Diaoyu Dao in international relations in the Ming Dynasty

China and Ryukyu started to engage in exchanges in the Ming Dynasty. In the first lunar month of the fifth year of the Hongwu reign (1372), the Ming court sent Yang Zai to Ryukyu as an envoy with an imperial edict. At that time, Chinese sailors could reach Ryukyu only via the Diaoyu Dao Islands following the navigation records of their predecessors. The name and use of Diaoyu Dao were officially confirmed and established in the 1370s. In the 300 years that followed, the Ming court sent 25 delegations to Ryukyu and Ryukyu dispatched some 300 delegations to pay tribute to the Ming Dynasty. The ensuring Qing Dynasty maintained the relationship with Ryukyu. China and Ryukyu conducted frequent exchanges for 500 years before the latter was annexed by Japan in 1879.

The five reports filed by envoys dispatched by the Ming court to confer titles on the Ryukyu king available today provide first-hand materials on the Ming Dynasty's establishment of sovereignty over Diaoyu Dao. The earliest record is found in Records of the Imperial Title-Conferring Envoys to Ryukyu (Shi Liu Qiu Lu) written in 1534 by Chen Kan, which clearly stated that "the ship has passed Diaoyu Dao, Huangmao Yu, Chi Yu... Then Gumi Mountain comes into sight, which is where the land of Ryukyu begins." This shows the Gumi Mountain, now known as the Kume Island, served as the border between China and Ryukyu. The document also said that Ryukyu people on the ship thought they were back home when seeing the Gumi Mountain, evidence that they considered the Gumi Mountain as their territory. The report of another imperial envoy of the Ming Dynasty, Guo Rulin, written in 1562, also stated that "Chi Yu is the mountain that marks the boundary of Ryukyu," indicating Chi Yu, now known as Chiwei Yu, was on China's border with Ryukyu. These documents show that the islands, with Chiwei Yu as the outermost point—including Diaoyu Dao—were territories of the Ming Dynasty.

Shi Liu Qiu Lu written by Xiao Chongye and Xie Jie in 1579 reaffirmed the maritime border between China and Ryukyu. Xie also said in his book Addendum to Summarized Record of Ryukyu (Liu Qiu Lu Cuo Yao Bu Yi) that he entered Ryukyu from Cang Shui to Hei Shui, and returned to China from Hei Shui to Cang Shui, the earliest record of the Ryukyu Trench, today's Okinawa Trough. Xia Ziyang, another imperial envoy of the Ming court, highlighted the Hei Shui Gou between the Gumi Mountain and Chiwei Yu as the natural border between China and Ryukyu. He wrote in his report in 1602 that "when the water flows from Hei Shui back to Cang Shui, it enters the Chinese territory." In 1633, Hu Jing once again clarified that the Gumi Mountain was the border of Ryukyu in his book A Record of Ryukyu (Liu Qiu Ji).

Title-conferring envoys of the Qing Dynasty also chronicled their missions in a number of documents, including Accounts of the Imperial Title-Conferring Envoys to Ryukyu (Shi Liu Qiu Ji) by Zhang Xueli in 1663, Miscellaneous Records of a Mission to Ryukyu (Shi Liu Qiu Za Lu) by Wang Ji in 1683, Records of Messages From Chong-shan (Zhong Shan Chuan Xin Lu) by Xu Baoguang in 1719, Annals of Ryukyu (Liu Qiu Guo Zhi Lue) by Zhou Huang in 1756, Shi Liu Qiu Ji by Li Dingyuan in 1800 and A Sequel to Annals of Ryukyu (Xu Liu Qiu Guo Zhi Lue) by Qi Kun and Fei Xizhang in 1808. Without exception, all these documents show Diaoyu Dao and its affiliated islands belonged to China.

That Diaoyu Dao belonged to China was an international consensus in East Asia during Ming and Qing dynasties. Diaoyu Dao and its affiliated islands were not seen on the map of the 36 Ryukyu Islands in A Record of States East of the Sea (Hai Dong Zhu Guo Ji) by Korean scholar Sin Sukju or on the map of these islands drawn based on discussions between Chinese and Ryukyu representatives in Xu Baoguang's Zhong Shan Chuan Xin Lu. In 1650, Annals of Chong-shan (Zhong Shan Shi Jian), the first official history of the Ryukyu Kingdom, quoted descriptions of Diaoyu Dao from Chen Kan's Shi Liu Qiu Lu. Precious Documents of Successive Generations (Li Dai Bao An), an archive of Ryukyu's royal family, did not mention Diaoyu Dao and its affiliated islands. These facts show Ryukyu people never considered these islands as their territories. In his 1721 book A Record of Southern Islands (Nan Dao Zhi), Japanese scholar Arai Hakuseki did not include Diaoyu Dao and its affiliated islands when describing the 36 Ryukyu Islands, the borders of the Ryukyu Kingdom and the islands under its jurisdiction.

China has exercised effective jurisdiction over Diaoyu Dao since the 1370s

Diaoyu Dao and its affiliated islands were not terra nullius, but have long been under China's sovereign jurisdiction.

By the early Ming Dynasty in the 1370s, China had carried out effective jurisdiction over Diaoyu Dao and its affiliated islands, with maritime patrols providing strong evidence. In 1372, the fifth year of the Hongwu reign, the Ming court ordered Zhejiang and Fujian provinces to build ships to combat pirates. According to Veritable Records of Emperor Taizu of the Ming Dynasty (Ming Tai Zu Shi Lu), fleets led respectively by Zhang He, Marquis of Ocean Navigation, and Wu Zhen, Marquis of Ocean Tranquility, patrolled the East China Sea up to the "Ryukyu Ocean." For instance, Zhang's fleet encountered pirates during a patrol in 1373. Zhang chased them to the "Ryukyu Ocean," killed many pirates and seized their weapons before returning home. In the following year, Wu led another anti-piracy patrol, during which coastal defense forces in southeast China were all under his command.

Large-scale patrols lasted for more than a year and a half. During one of the patrols, the Chinese fleet reached the "Ryukyu Ocean," captured several pirate boats and brought the captives to Beijing. The "Ryukyu Ocean," now known as the Okinawa Trough, was the natural border between China and Ryukyu as clarified in the reports of envoys sent by the Ming court to Ryukyu. Maritime patrols in the early Ming Dynasty show Diaoyu Dao and its affiliated islands were covered not only by the coastal defense system of Fujian but also by the national coastal defense system of the Ming Dynasty.

As pirates ran rampant during the Jiajing reign of the Ming Dynasty, coastal defense maps gained popularity. An Illustrated Compendium on Maritime Security (Chou Hai Tu Bian) compiled by Zheng Ruozeng under the auspices of Hu Zongxian, Supreme Commander of the southeast coastal defense of the Ming court, went to the press in 1562, the 41st year of the Jiajing reign. It is the earliest and most detailed ancient coastal defense atlas that remains available today. In this book, Diaoyu Dao, the Huangmao Mountain (Huangwei Yu) and Chi Yu (Chiwei Yu) appeared on the Map of Coastal Mountains and Sands (Yan Hai Shan Sha Tu) and were marked as under the jurisdiction of the coastal defense of Fujian Province. The map shows the Diaoyu Dao Islands had been incorporated into China's scope of jurisdiction by the Ming Dynasty.

Official and unofficial coastal defense atlases published in the following years, including A Mirror of Japan (Ri Ben Yi Jian) by Zheng Shungong in 1565, A Truthful Record of Pirates (Qian Tai Wo Zuan) by Xie Jie in 1595, The Complete Map of Unified Maritime Territory for Coastal Defense (Qian Kun Yi Tong Hai Fang Quan Tu) by Xu Bida in 1605, An Overview of Coastal Defense (Hai Fang Zuan Yao) by Wang Zaijin in 1613 and Treatise on Military Preparations (Wu Bei Zhi) by Mao Yuanyi in 1621, all documented the route from Fujian to Ryukyu. They provided evidence that Diaoyu Dao and its affiliated islands were not Ryukyu's territories or terra nullius, but fell under the scope of the Fujian coastal defense, belonging to Chinese territory.

The entry about "setting off from Diaoyu Tai" in San Shi Liu Xing Suo Chuan Zhen Ben is the most noteworthy because it shows Diaoyu Dao was not only an important navigational marker but also a major destination of Chinese seafarers in the Ming Dynasty. A Tour of Duty in the Taiwan Straits (Tai Hai Shi Cha Lu) written by Huang Shujing in 1722 described Diaoyu Tai as a port when recounting a tour of an imperial inspector to Taiwan, descriptions that were widely quoted in Taiwan's local chronicles. Maps such as the Great Universal Geographic Map (Kun Yu Quan Tu) created during the Qianlong reign (1736-1795) of the Qing Dynasty also show the Diaoyu Dao Islands were China's territories in Ming and Qing dynasties, during which China exercised long-term effective jurisdiction over the islands.

In conclusion, Diaoyu Dao, first discovered and named by Chinese people, has been under the effective jurisdiction of successive Chinese governments. It is therefore clear that the island belongs to China. Diaoyu Dao and its affiliated islands were not terra nullius long before they were illegally occupied by Japan at the end of the 1800s. Ming and Qing literature provides ample historical evidence that these islands have been inherent Chinese territories under the administration of the Chinese Government since the 1370s. China's sovereignty over the islands is indisputable.

(The author is a research fellow with the Institute of History at the Chinese Academy of Social Sciences)