10世紀紅河デルタ開拓試論(<特集>東南アジア低地開拓史 : 東南アジアにおける低地開発の諸相)

Abstract

This essay is about the state of rice agriculture in the Red River Delta in the tenth century, and is the second part of the historical study of the reclamation of that delta from the first century to the nineteenth century, which aims at understanding the characteristics of Vietnamese socioeconomical history in comparison with other Southeast Asian deltas. In Part 1, the identification of Duong Lam, the home base of Ngo Quyen, the first founder of a Vietnam independent of China, and Tien Du and Vu Ninh, the domains of the Su Quan (Twelve Lords), with present place names, it is shown that the economic power of those lords in the tenth century was based on rice cultivation on terrace and foothill areas, which can be traced back to the first reclamation period of the delta, conjectured to be in the Dong Son age. In Part 2, by analysis of the situation of Co Phap, the home village of Ly Cong Uan, the first emperor of Ly Dynasty, Xieu Loai, Phong Chau, and Nguyen Gia, domains of the Su Quan, Mat Lien, and Phu Dai, fiefs of the sons of Le Hoan, the first emperor of the Early Le Dynasty, I conclude that their influence was founded on the natural levees along big rivers such as the Red River, Canal des Rapides and Canal des Bambous, which would make them almost the same in character as the lands and power base of native powers, that is dating from the first reclamation period. In Part 3, however, Hong Chau, the home village of the Khuc family, the first native governors of Giao Chau (North Vietnam) when independent of China, Do Dong Giang, a domain of the Su Quan, and Dai De, home village of Do Thich, an assassin of Dinh Bo Linh, one finds that a new reclamation type appeared on the small natural levees located in the western flood area (casier de Hadong) and the upper delta with the adoption of fifth-month rice cultivation in these lower-lying fields. In Part 4, in other cases such as Chuong Duong, a fief of Duong Tham Kha, a usurper of the throne from the Ngo family, and Dang Chau, a domain of the Su Quan, a tendency to penetrate some sandbank areas to plant mulberry or for use as small navigation stations on the Red River is shown. In Part 5, I point out that in places at the edge of the Red River Delta, such as Hoa Lu, the capital of the Dinh and Le dynasties, Bo Hai Khau, a domain of the Su Quan, Tra Huong, a base of Pham Linh Cong, a patron of a son of Ngo Quyen, and Hoi Ho, a domain of the Su Quan, a new type of political power had risen during the tenth century. These areas were not suitable for rice cultivation without dikes. So it is very difficult to explain the existence of powers in these areas by agricultural factors alone. One can suppose that more important to these lords would be control of navigation on the Red River, Song Day River and the Thai Binh-Canal des Rapides river system. In conclusion, in the tenth century, the reclamation of the Red River Delta was an extension of a traditional agronomic method introduced in the Dong Son age, especially in the Trung Du area (the middle part of the Red River Valley), and some commercial factors were introduced onto this base. However, this conclusion suggests that reclamation methods would be limited by the geographical situation. So, a new engineering method had to be introduced to reclaim such unfavorable areas as backswamps and tidal creeks. This happened from the tenth century with the power of new dynasties to mobilize manpower and the introduction of the dike construction method newly developed in the Yangtze River Delta during the Sung Dynasty. This can be regarded as the first application of engineering methods to reconstruct the delta geography for rice cultivation. This topic will be discussed in the third report of this series.