Areas comprising what is now Brunei participated in the Maritime Jade Road, as ascertained by archaeological research. The trading network existed for 3,000 years, between 2000 BC to 1000 AD.[33][34][35][36] The settlement known as Vijayapura was a vassal-state to the Buddhist Srivijaya empire and was thought to be located in Borneo's Northwest which flourished in the 7th Century.[37] Vijayapura itself upon earlier in its history, was a rump state of the fallen multi-ethnic: Austronesian, Austroasiatic and Indian, Funan Civilization; previously located in what is now Cambodia.[38]: 36  This alternative Srivijaya known as Vijayapura referring to Brunei, was known to Arabic sources as "Sribuza".[39] One of the earliest Chinese records of an independent kingdom in Borneo is the 977 AD letter to the Chinese emperor from the ruler of Boni, which some scholars believe to refer to Borneo.[40] The Bruneians regained their independence from Srivijaya due to the onset of a Javanese-Sumatran war.[41] In 1225, the Chinese official Zhao Rukuo reported that Boni had 100 warships to protect its trade, and that there was great wealth in the kingdom.[42] Marco Polo suggested in his memoirs that the Great Khan or the ruler of the Mongol Empire, attempted and failed many times in invading "Great Java" which was the European name for Bruneian controlled Borneo.[43][additional citation(s) needed] According to Wang Zhenping, in the 1300s, the Yuan Dade nanhai zhi or "Yuan dynasty Dade period southern sea records" reported that Brunei conquered or administered Sarawak and Sabah as well as the Philippine kingdoms of Butuan, Sulu, Ma-i (Mindoro), Malilu 麻裏蘆 (Manila), Shahuchong 沙胡重 (Siocon or Zamboanga), Yachen 啞陳 Oton, and 文杜陵 Wenduling (Mindanao),[44] which would regain their independence at a later date.[45] In the 14th century, the Javanese manuscript Nagarakretagama, written by Prapanca in 1365, mentioned Barune as the constituent state of Hindu Majapahit,[46] which had to make an annual tribute of 40 katis of camphor. In 1369, Sulu which was also formerly part of Majapahit, had successfully rebelled and then attacked Boni, and had invaded the Northeast Coast of Borneo[47] and afterwards had looted the capital of its treasure and gold including sacking two sacred pearls. A fleet from Majapahit succeeded in driving away the Sulus, but Boni was left weaker after the attack.[48] A Chinese report from 1371 described Boni as poor and totally controlled by Majapahit.[49] When the Chinese admiral Zheng He visited the Brunei in the early 15th century, he founded a major trading port which included Chinese people who were actively trading with China.[50] During the 15th century, Boni had seceded from Majapahit and then converted to Islam. Thus transforming into the independent Sultanate of Brunei. Brunei became a Hashemite state when she allowed the Arab Emir of Mecca, Sharif Ali, to become her third sultan. As customary for close affiliation and alliances in Southeast Asia, the royal family of Luzon intermarried with the ruling houses of the Sultanate of Brunei.[51] Intermarriage was a common strategy for Southeast Asian states to extend their influence.[52] However, Islamic Brunei's power was not uncontested in Borneo since it had a Hindu rival in a state founded by Indians called Kutai in the south which they overpowered but didn't destroy. Nevertheless, by the 16th century, Islam was firmly rooted in Brunei, and the country had built one of its biggest mosques. In 1578, Alonso Beltrán, a Spanish traveller, described it as being five stories tall and built on the water.[53] War with Spain and decline[edit] Brunei territorial losses from 1400 to 1890 Brunei briefly rose to prominence in Southeast Asia when the Portuguese occupied Malacca and thereby forced the wealthy and powerful but displaced Muslim refugees there to relocate to nearby Sultanates such as Brunei. The Bruneian Sultan then intervened in a territorial conflict between Hindu Tondo and Muslim Manila in the Philippines by appointing the Bruneian descended Rajah Ache of Manila as admiral of the Bruneian navy in a rivalry against Tondo and as the enforcer of Bruneian interests in the Philippines. He subsequently encountered the Magellan expedition[54] wherein Antonio Pigafetta noted that under orders from his grandfather the Sultan of Brunei, Ache had previously sacked the Buddhist city of Loue in Southwest Borneo for being faithful to the old religion and rebelling against the authority of Sultanate.[55] However, European influence gradually brought an end to Brunei's regional power, as Brunei entered a period of decline compounded by internal strife over royal succession. In the face of these invasions by European Christian powers, the Ottoman Caliphate aided the beleaguered Southeast Asian Sultanates by making Aceh a protectorate and sending expeditions to reinforce, train and equip the local mujahideen.[56] Turks were routinely migrating to Brunei as evidenced by the complaints of Manila Oidor Melchor Davalos who in his 1585 report, say that Turks were coming to Sumatra, Borneo and Ternate every year, including defeated veterans from the Battle of Lepanto.[57] Spain declared war in 1578, planning to attack and capture Kota Batu, Brunei's capital at the time. This was based in part on the assistance of two Bruneian noblemen, Pengiran Seri Lela and Pengiran Seri Ratna. The former had travelled to Manila, then the centre of the Spanish colony. Manila itself was captured from Brunei, Christianised and made a territory of the Viceroyalty of New Spain which was centered in Mexico City. Pengiran Seri Lela came to offer Brunei as a tributary to Spain for help to recover the throne usurped by his brother, Saiful Rijal.[58] The Spanish agreed that if they succeeded in conquering Brunei, Pengiran Seri Lela would be appointed as the sultan, while Pengiran Seri Ratna would be the new Bendahara. Chinese depiction of delegates from Brunei arriving in Beijing. From the Ten Thousand Nations Coming to Pay Tribute, 1761 In March 1578, a fresh Spanish fleet had arrived from Mexico and settled at the Philippines. They were led by De Sande, acting as Capitán-General. He organised an expedition from Manila for Brunei, consisting of 400 Spaniards and Mexicans, 1,500 Filipino natives, and 300 Borneans.[59] The campaign was one of many, which also included action in Mindanao and Sulu.[60][61] The racial make-up of the Christian side was diverse since it were usually made up of Mestizos, Mulattoes and Amerindians (Aztecs, Mayans and Incans) who were gathered and sent from Mexico and were led by Spanish officers who had worked together with native Filipinos in military campaigns across the Southeast Asia.[62] The Muslim side was also equally racially diverse. In addition to the native Malay warriors, the Ottomans had repeatedly sent military expeditions to nearby Aceh. The expeditions were composed mainly of Turks, Egyptians, Swahilis, Somalis, Sindhis, Gujaratis and Malabars.[63] These expeditionary forces had also spread to other nearby Sultanates such as Brunei and had taught new fighting tactics and techniques on how to forge cannons.[64] Eventually, the Spanish captured the capital on 16 April 1578, with the help of Pengiran Seri Lela and Pengiran Seri Ratna. The Sultan Saiful Rijal and Paduka Seri Begawan Sultan Abdul Kahar were forced to flee to Meragang then to Jerudong. In Jerudong, they made plans to chase the conquering army away from Brunei. Suffering high fatalities due to a cholera or dysentery outbreak,[65][66] the Spanish decided to abandon Brunei and returned to Manila on 26 June 1578, after 72 days.[67] Pengiran Seri Lela died in August or September 1578, probably from the same illness suffered by his Spanish allies.[