Transriver Borders in the Asian Highlands

Asian Highlands rivers flow down to the world’s most heavily populated river plains in South, Southeast, and East Asia. These well-watered, sediment-rich plains have attracted human settlers for millennia. For most of this history, the powerful states that ruled the river plains left highland states and communities alone, and within the highlands, shifting mosaics of states and independent communities governed river valleys. These highlanders’ border practices only restricted the movement of armies and untaxed trade but allowed flows of nomads, animals, and rivers. This system began to change during the mid-19th century, as the British, Russian, and Manchu-Qing empires began drawing competitive maps that claimed overlapping areas of the highlands. Over the next century, the British and Chinese increased their control of the highlands, and from the 1950s onward, the postcolonial Chinese, Indian, and Pakistani states attempted to enforce the ill-defined imperial-era borders on the ground. This territorialization transformed cartographic disputes into actual and threatened conflict as all three nations built up armies and infrastructure in the highlands. By the early 21st century, all three states were maintaining strict, militarized, and monitored bordering practices. The states’ bordering practices transected the Indus, Ganges-Brahmaputra, Salween, Mekong, and Yangzi River Systems. As the rivers preceded the borders, they should be known as transriver boundaries, but as much history and commentary are focused on nation-states, the waterways ahistorically tend to be called transboundary rivers.