Irrigation in the western region of Cochinchina under the Nguyen Dynasty (1802-1867)

Abstract

In the first half of the 19th century, when regional relations had many fluctuations, the Nguyen Dynasty implemented the resolute policies to protect the Southwest border and dug canals along the border to defend the territory. The responsibility and obligation to protect the sovereignty of the military force were strictly regulated in the Gia Long Code completed in the 11th Gia Long year (Lunar year 1812). The Nguyen Dynasty made the total land recording directory of the entire Luc Nam Ky province (1836), established and consolidated the administrative organization, and completed the social management apparatus from the village (commune) to the intermediate local administrative unit between a district and a commune, district, and province. In addition to the administrative apparatus, the Theravada Buddhist pagoda of the Khmer, cultural institutions, and folk beliefs of the Vietnamese were formed and operated: the tutelary deity temple, the Taoist temple, and the Mahayana Buddhist pagoda. The institutions, cultural facilities, and folk beliefs help calm people's minds, stabilize society, and contribute to the exercise of Vietnam's sovereignty over new lands. The digging of canals, embankment of roads, and development of water and road transport such as Thoai Ha canal (1817), Vinh Te canal (1819-1824), and Vinh An canal (1843-1844) created artificial moats combined with natural ones to protect the territory. Facing the invading force of the French colonialists, the Nguyen Dynasty gradually ceded the provinces of Cochinchina to the French in 1862, 1867, and 1874 although this showed the inability of the Nguyen Dynasty, legally, especially in the international legal sense, these treaties are evidence of Vietnam's indisputable territorial sovereignty over the land of Cochinchina. France could not sign a treaty dividing part of a country's territory if the country did not have sovereignty over that territory, which proved the ingenious leadership of the Nguyen Dynasty at that time, specifically King Minh Mang. Although he was in Phu Xuan capital (Hue), he extended his power to the whole country, carried out a drastic administrative reform, and reorganized the entire state apparatus under the Nguyen Dynasty. Thanks to that, Dai Nam became a country that unified administrative territories and rituals from the exercise of sovereignty over the islands in the South China Sea.