Bruneian–Igan War

The Bruneian–Igan War, was a military conquest of Igan and later a military invasion to their allies by the Bruneian Sultanate in the 14th century. The conquest resulted in the destruction of Igan and their allies and opened the door for further Bruneian expansion over Borneo.

Background
At the beginning, Melanau and Brunei were both subjects of the Majapahit Empire. A number of regions, including "Kadangdangan, Landa Samedang, Tirem, Sedu, Barune(ng), Kalka, Saludung, Solot, Pasir Barito, Sawaku, Tabulang, Tajung Kuteri, and Malano," were vassals of the Majapahit, according to the old Nagarakretagama record. As the Majapahit Empire collapsed, Brunei seized the chance to increase its power and set its sights on the Tutong River region. Pembakal Bangis, a Bruneian nobleman, was chosen by Awang Alak Betatar to make the request that Mawangga, the Tutong chief, show up at the capital. Mawangga responded, however, that he and his people were conquered slaves, ruled by the Melanau leader Basiung and his in-law Tugaw, who resided in Igan, and that they could not submit.

Causes
Mawangga told Pembakal Bangis that Tutong would surrender to the authority of the Brunei King if the great Melanau commander, Awang Alak Betatar, ordered his soldiers to proceed to Igan. Awang Alak Betatar's demand was communicated to Basiung, the chief of the Bruneian forces at Igan. However, Basiung was not pleased and was used to people approaching him. In response, Basiung suggested that Awang Alak Betatar pay him a visit instead, threatening to launch an Igan attack on Brunei if there was any delay. Bangis told Basiung nine days to make up his mind, but Basiung was unfazed and declared that he would make sure Awang Alak Betatar didn't hurt him if he showed up on time with presents. Awang Alak Betatar and his ministers, Awang Semaun, Awang Jeramabak, and Pateh Damang Sari, were offended by Basiung's reply and chose to attack Igan in order to establish their authority.

War
The first battle between Brunei and foreign armies was the Battle of the Igan Valley. The Igan River flowed through this valley and was located in the traditional lands of the Melanau-speaking people. There are two accounts of the fight: the first, more legendary, tells of a nine-month struggle between three Brunei heroes and Bilanapura, a genie that Jerambak finally defeated using a miraculous fish skin he stole from an ogre. According to the second, Awang Jerambak's Brunei men came up against Basiung and his 9,000-strong allied armies from Sambas, Matu, Sadung, and Sarikei. The Brunei army, aided by the Dayaks, overpowered Basiung's warriors despite their superior numbers; as a result, Igan was destroyed and war spoils were taken. Following this, Jerambak made Igan accept Awang Alak Betatar's dominance.

The Bruneian soldiers persisted in their conquests, subduing Igan's allies, such as Sarikei, Rajang, Sadung, Sarawak, Tanjung Datu, and Lingga, and stealing and capturing the traditionally Melanau regions of Oya, Matu, and Mukah.

Aftermath
As a result of this victory, Brunei expanded it's dominion to modern day Sarawak, it later expanded further and finally reached its peak during the reign of Sultan Bolkiah.