Final answer:
The sultanate on the coast of Borneo that was formerly under British protection is Brunei. It is known for its oil and natural gas reserves and became independent in 1984.
Step-by-step explanation:
The sultanate on the coast of Borneo that was formerly under British protection is Brunei. This small Sultanate consists of two separate regions along the coast of the South China Sea. Brunei gained its independence from British rule in 1984 and has since been known for its vast reserves of oil and natural gas, which have provided its citizens with a high standard of living.
The country's economy is heavily dependent on the energy sector, and its future may involve developing strategies, such as establishing a free trade zone, to maintain wealth after the depletion of these natural resources.