Capitals: Kota Batu, Mapong Ayer, Brunei Town
Official Languages: Brunei Malay, Old Malay, Old Tagalog, Arabic, Bornean
Established: 1368 AD/CE
Disestablished: 1888 AD/CE
The earliest diplomatic relations between Boni (渤泥) and China are recorded in the Taiping Huanyu Ji (太平環宇記) (978). In 1178, a mission to China sent by Srivijaya include forest product from Borneo such as plum flower-shaped Borneo camphor planks, which highlighted the Srivijaya's role as intermediary to acquire Borneo product. In 1225, a Song dynasty official, Zhao Rukuo, reported that Boni had 10,000 population who populated a city surrounded by a timber wall, and having 150 warships to protect its trade, and that there was a lot of wealth in the kingdom. Zhao Rukuo noted that smaller riverine systems in Borneo are traded with Boni in smaller vessel; they are Xi Fenggong (River Serudong), Shimiao (Sibu), Hulumandou (Martapura and Suwulu (Matan). These are sub-regional port of Borneo network located in west and south coast of Borneo.
In the 14th century, Brunei seems to be subjected to Java. The Javanese manuscript Nagarakretagama, written by Prapanca in 1365, mentioned Barune as the vassal state of Majapahit, which had to make an annual tribute of 40 katis of camphor.
In 1369, the Sulus attacked Po-ni, looting it of treasure and gold. A fleet from Majapahit succeeded in driving away the Sulus, but Po-ni was left weaker after the attack. A Chinese report from 1371 described Po-ni as poor and totally controlled by Majapahit.
After the death of its emperor, Hayam Wuruk, Majapahit entered a state of decline and was unable to control its overseas possessions. This opened the opportunity for Bruneian kings to expand their influence.
In 1370, Brunei received an imperial emissary from the Ming Empire, which sought to re-establish the Song dynasty tributary system. In 1371, Brunei established a tributary relationship with the Ming. During the 1370 visit, Ming observers noted the Islamisation of Brunei to be limited to only a section of the royal entourage, while Buddhism was spreading in the general populace. Despite the establishment of Ming suzerainty, Brunei did not pay much attention to Ming decrees until 1403, when the Yongle Emperor rapidly strengthened among maritime trade policies. Brunei ceased to be a tributary state of the Ming in 1425.
By the 15th century, the empire became a Muslim state, when the King of Brunei converted to Islam, brought by Muslim Indians and Arab merchants from other parts of Maritime Southeast Asia, who came to trade and spread Islam. It controlled most of northern Borneo, and it became an important hub for the East and Western world trading system. Local historians assume that the Bruneian empire was a thalassocratic empire that was based upon maritime power, which means its influence was confined to coastal towns, ports and river estuaries, and seldom penetrated deep into the interior of the island. The Bruneian kings seem to have cultivated alliance with regional seafaring peoples of Orang Laut and Bajau that formed their naval armada. The Dayaks, native tribes of interior Borneo however, were not under their control, as imperial influence seldom penetrated deep into the jungles.
Following the presence of Portuguese after the fall of Malacca, Portuguese merchants traded regularly with Brunei from 1530 and described the capital of Brunei as surrounded by a stone wall.
During the rule of Bolkiah, the fifth Sultan, the empire held control over coastal areas of northwest Borneo (present-day Brunei, Sarawak and Sabah) and reached Seludong (present-day Manila), Sulu Archipelago including parts of the island of Mindanao. In the 16th century, the Brunei empire's influence extended as far as Kapuas River delta in West Kalimantan. The Malay Sultanate of Sambas in West Kalimantan and Sultanate of Sulu in Southern Philippines in particular developed dynastic relations with the royal house of Brunei. Other Malay sultans of Pontianak, Samarinda as far as Banjarmasin, treated the Sultan of Brunei as their leader. The true nature of Brunei's relations to other Malay Sultanates of coastal Borneo and Sulu archipelago is still a subject of study, as to whether it was a vassal state, an alliance, or just a ceremonial relationship. Other regional polities also exercised their influence upon these sultanates. The Sultanate of Banjar (present-day Banjarmasin) for example, was also under the influence of Demak in Java.
By the end of 17th century, Brunei entered a period of decline brought on by internal strife over royal succession, colonial expansion of the European powers, and piracy. The empire lost much of its territory due to the arrival of the western powers such as the Spanish in the Philippines, the Dutch in southern Borneo and the British in Labuan, Sarawak and North Borneo. By 1725, Brunei had many of its supply routes had been taken over by the Sulu Sultanate.
In 1888, Sultan Hashim Jalilul Alam Aqamaddin later appealed to the British to stop further encroachment. In the same year British signed a "Treaty of Protection" and made Brunei a British protectorate until 1984 when it gained independence.