Here is an interesting alternative account of the Sulu claim over Sabah from the Brunei perspective. As attested by early modern accounts of written history in Brunei, it is noted that the Sulu were given possession of Sabah or parts of Sabah for help rendered to Sultan Muhydin, the 14th Sultan of Brunei who fought a civil war against the 13th Sultan of Brunei, Sultan Abdul Mubin. However, there are other sources which disputes this and claims that Sabah had always belonged to Brunei.
Interestingly enough, Pehin Jamil Umar writing in his book, Tarsilah Brunei II: Period of Splendour and Fame (2007), countered all of the above. Pehin Jamil did not deny the fact that the Sulus were invited and promised the northern Brunei territory by Sultan Muhydin if they helped him win the civil war against Sultan Abdul Mubin. However, during the battle for Pulau Cermin, the Sulu forces who were supposed to attack the island from Pulau Keingaran and from the sea, did not do so. They were terrified by the resistance of Sultan Abdul Mubin’s forces in Pulau Cermin. It was only after Sultan Muhydin had won the battle did the Sulu forces landed and took the opportunity to seize a number of war booties.
According to Pehin Jamil, Sultan Muhydin refused to cede the territories claimed by Sulu. Pehin Jamil noted that the area was only “claimed” and not “ceded”, as Sir Stamford Raffles, in his book “History of Java” (1830), had noted “on the north-east of Borneo proper (Brunei) lies a very considerable territory (Sabah), the sovereignty of which has long been claimed by Sulu Government”.
Pehin Jamil further noted that according to the oral tradition, Sulu continued to press their claim. In 1775, one of their chiefs came to Brunei pretending to seek fresh water. What they really wanted was to seek an audience with the Sultan regarding Sabah. However, the Sultan ordered one of the chief wazirs to see them and he threatened that if they wanted to pursue their intention, he will kill them all. The Sulus immediately left. Despite that setback, the Sulus continue to maintain their claims.
The argument that Brunei has not ceded Sabah to Sulu is supported by LR Wright in her book The Origins of British Borneo (1970). She wrote: “indeed, the legitimacy of the Sulu claim to the territory (North Borneo) is in considerable doubt partly because of the unreliability of tarsilas such as ‘Selesilah’, which in many cases are nothing more than written-down legends to enhance the status of the royal house which produced them. Succeeding Sultans of Brunei have denied that northern Borneo was given to Sulu, and only the weight of Sulu tradition supports the claim. The weight of Brunei tradition challenges it”.