evidence: Brunei covers only some 2,226 square miles (5,765 square kilometers), but in the early sixteenth century, when it was already an Islamic sultanate, its control extended over the entire northwestern area of the island of Borneo, including the present-day Malaysian states of Sabah and Sarawak, and some portions of the Sulu islands in the southern Philippines. Spanish explorers were the first Europeans to visit the sultanate of Brunei, and trade with Europe quickly ensued. Internal strife brought on by conflicts over royal succession, and colonial expansion by European powers, caused a period of decline. By the end of the eighteenth century, Brunei was known as a haven for marauding pirates. Predominant British influence began in 1849, when the British, looking for a way to protect their lucrative trade between Singapore and northwest Borneo, took action against the pirate fleets and disabled them within five years. Previous British influence in the region had come from a British officer, Sir James Brooke (1803–1868), who was instrumental in helping the Sultan of Brunei quell a civil war; in 1841 the grateful sultan ceded to Brooke the state of Sarawak.