The Apostolic Vicariate of Brunei Darussalam caters to a small nation on the northern coast of Borneo. The vicariate is headed by an apostolic vicar, presently Bishop Cornelius Sim.
The population of Brunei Darussalam was estimated at 459,000, in 2017.
The majority Malays include the indigenous communities of Kedayan, Tutong, Belait, Bisaya, Dusun and Murut, accounting for 237,100 people. Members of other indigenous groups account for 12,300 people, the Chinese (40,200), and the other races (68,200).
The official language is Malay. Other languages include English and Chinese.
The present Catholic community in the country traces its roots to the Missionary Society of St. Joseph (Mill Hill Missionaries). Throughout the years, the local Church was administered by various ecclesiastical jurisdictions centered in Labuan, Jesselton (now Kota Kinabalu), Kuching and Miri, cities in neighboring Malaysia.
The separation of the Bruneian territory, formerly under the Diocese of Miri-Brunei (now simply known as the Diocese of Miri), created a distinct Bruneian Church. The new territory was designated as an apostolic prefecture in November 1997.
The Apostolic Prefecture of Brunei Darussalam came into being on February 22, 1998. On October 20, 2004, less than seven years after it was formed, the apostolic prefecture was elevated to an apostolic vicariate.
Brunei Darussalam has an equatorial climate, characterized by a uniform high temperature, high humidity and heavy rainfall. Temperatures range from 23-32 degree Celsius, while rainfall varies from 2,500 mm annually on the coast to 7,500 mm in the interior. There is no distinct wet season.
The land surface is developed on bedrock of tertiary age, comprising sandstone, shale and clay. The terrain in the western part of Brunei Darussalam is predominantly hilly lowland below 91 m, but rising in the hinterland to about 300 m. The eastern part of the state consists predominantly of rugged mountain terrain, rising 1,850 m above sea level, at Bukit Pagon. The coast has a wide, tidal and swampy plain.
Islam is the official religion of Brunei Darussalam as stated in the Constitution, with His Majesty the Sultan as Head of the State. Islam plays a central role in the life of Brunei Darussalam. Other faiths practiced include Christianity and Buddhism.
Brunei Darussalam is situated on the north-west of the island of Borneo. It has a total area of 5,765 sq. km. with a coastline of about 161 km along the South China Sea. It is bounded on the north by the South China Sea and on all the other sides by the Malaysian state of Sarawak.
Brunei Darussalam is divided into four districts namely Brunei/Muara, Tutong, Belait and Temburong. Bandar Seri Begawan is the capital of Brunei Darussalam with an area of about 16 sq. km. The famed Water Village of Brunei (Kampong Ayer) is also located here.
The vicariate does not operate a distinct chancery, nor does it have a designated cathedral. However, one of the parishes, the Church of Our Lady of the Assumption, unofficially hosts both functions, as it is the residence and office of the bishop, and is the most populous parish in the vicariate. There is no official priests' council, although the clergy meet on a monthly basis.
The vicariate is administered pastorally through commissions responsible for liturgy, catechetics, finance, education, the youth, evangelization, family life, migrant welfare, the Bible apostolate and social communication.