In the absence of any other evidence, scholars have created an early history of Brunei that is mainly based on flexible interpretations of Chinese texts. This early part reads: Chinese records from the sixth century mention a state called P’o-li on the northwest coast of Borneo.[17] In the seventh century, Chinese and Arab accounts state a place called Vijayapura, which was thought to be founded by members of the royal family of Funan.[18] They were believed to have landed on the northwest coast of Borneo with some of their followers. They then captured P’o-li and renamed the territory 'Vijayapura' (meaning 'victory' in Sanskrit). In 977, Chinese records started to use Po-ni instead of Vijayapura to refer to Brunei.[19] In 1225 a Chinese official named Chua Ju-Kua reported that Brunei has 100 warships to protect its trade and that there was a lot of gold in the kingdom.[20] Another report in 1280 described Po-ni as controlling large parts of Borneo Island (modern day Sabah and Sarawak, Sulu and some parts of the Philippines).
In the fourteenth century, Po-ni became a vassal state of Majapahit, and had to pay an annual payment of 40 katis of camphor. Po-ni was attacked and looted of its treasure and gold by the Sulus in 1369. A fleet from Majapahit succeeded in driving away the Sulus but Po-ni became much weaker after the attack.[21] A Chinese report of 1371 described Po-ni as poor and totally controlled by Majapahit.[22] The power of the Sultanate of Brunei was at its peak between the 15th and 17th centuries, with its power extending from northern Borneo to the southern Philippines.[5] 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 traveler described it as being five stories tall and built on the water.[23]