The Sultanate of Brunei (Full name: Negara Brunei Darussalam) is a small but - thanks to natural gas and petroleum resources - very rich country located in Southeast Asia. It is surrounded by Malaysia and has two parts physically separated by Malaysia, almost being an enclave. Strategically located on the South China Sea, close to vital sea lanes linking Indian and Pacific Oceans, it has an exclusive economic fishing zone that extends as far as Louisa Reef in the southern Spratly Islands although it makes no public territorial claim to the offshore reefs.

The Sultanate of Brunei's heyday occurred between the 15th and 17th centuries, when its control extended over coastal areas of northwest Borneo and the southern Philippines. Brunei subsequently entered a period of decline brought on by internal strife over royal succession, colonial expansion of European powers, and piracy. In 1888, Brunei became a British protectorate. It was offered to join Malaysia as a state in 1963, but opted out of the Federation due to a disagreement on the amount of its oil income that would have to be given to the central government in Kuala Lumpur. Independence was achieved in 1984. The same family has ruled Brunei for over six centuries.