1. Islam in Brunei [By WIKIPEDIA]
Islam is Brunei's official religion, 64 percent of the population is Muslim. mostly Sunnis of Malay origin who follow the Shafi school of Islamic law. Most of the other Muslim groups are Kedayans (converts from indigenous tribal groups) and Chinese converts.

2. The golden history of Islam in Brunei
[By Rozan Yunos Mar 8th, 2010 . BANDAR SERI BEGAWAN]
Based on this fact alone, Abu Ali must have held an important position in the Brunei Government if he was tasked to be Brunei’s Ambassador in those days and even if the King of Brunei then was not himself a Muslim, some members of his royal court were Muslims. 

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