Due to the lack of fresh water, until the end of the 19th century, Bạch Long Vĩ Island was uninhabited and the island was just a place to avoid the strong wind of fishermen at sea. Around 1920, a freshwater well was discovered in the south of the island. In August 1921, a resident of Giap Nam village, Co To county, Quang Yen province made an application to be allowed to cultivate in the lowland area of Bạch Long Vĩ Island. Since then, the French protectorate had increased surveillance over the Bạch Long Vĩ and requested that the Department of Taxation's patrol boats departing from Co To Island must visit Bạch Long Vĩ at least once a year. In 1937, the Government of Emperor Bao Dai of Vietnam sent a squad of 12 men to form a garrison, established a village - commune (làng - xã) regime, appointed a village chief (Lý trưởng) on the island, and officially renamed the island is Bach Long Vi.