A newly-discovered historical map using both national boundary and administrative line to represent the U-boundary in the South China Sea

Abstract

A New Map of the People’s Republic of China was discovered through investigating a large number of historical maps. This map was published in April 1951, both continuous national boundary line and administrative region line were applied in this map to represent China’s national U shaped boundary line (U-boundary) in the South China Sea (SCS). It is an important historical material that supports the U-boundary line is the border of China’s South China Sea. This is the first research of this newly-discovered map. In the map, the U-boundary in the SCS (SCS U-boundary) is not only presented by a continuous boundary map symbol (·>—— —— This New Map of the People’s Republic of China was edited by the Guanghua and Geosciences Club and was published by SDX Joint Publishing Company. The continuous U-line in this map clearly shows the accurate boundaries of China’s border in the SCS. It is an important historical map that clearly proves the U-boundary line is the border of China’s territorial sea in the SCS. Moreover, the red solid administrative-line overlaying the U-boundary definitely indicated that the sovereignty of the sea within the U-boundary belonged to China. The regions of the SCS U-boundary include Dongsha Islands, Xisha Islands, Nansha Islands, Zhongsha Islands, Taiwan Island, Beibu Gulf and the Zengmu Reef. This study compared maps of historical U-line which were published before 1951, and also analyzed the domestic and international maritime situation, and drawing methods of the maritime boundary lines in the history. The results show that “the continuous line” was recognized by the international community in the corresponding historical period, and both the “intermittent (dotted) line” and “the continuous line” are appropriate descriptions and drawing-methods for the sea boundary in historical period. Analysis of six maps, including the historical maps and the latest vertical world map, showed that the territory of U-boundary line inherited the territory of China’s SCS in the “South China Sea Island Map” that was officially published and recognized worldwide in 1948. This study recommends using “the South China Sea U-Shape boundary line” (SCS U-boundary) to describe the border of China’s sea in SCS. “SCS U-boundary” not only emphasizes the U shape borderline of China’s sea in the SCS, but also can be easily expressed and remembered worldwide. Using “SCS U-boundary” is a better way to avoid problems of “number” and “number of segments”, and can further express the certainty of the integrity, continuity and border of the China’s seas in the SCS as well. In summary, the study points out: (1) SCS U-boundary is the border of China’s sea in the SCS, and its sovereignty belongs to China; (2) both “continuous U-boundary line” and “intermittent U-boundary line” are internationally recognized to describe sea borders; (3) “SCS U-boundary” is more vividly, accurately, completely and scientifically to characterize China’s sea border in the SCS.