This article focuses on the eastern region of the Red River Delta, Vietnam, between the tenth and sixteenth centuries. This area was an important centre of economic and population growth in aòi Viêòt in the thirteenth and fourteenth centuries, and nurtured aòi Viêòt's sophisticated and renowned ceramics industry, hosted leading schools of Vietnamese Buddhism and bred a rising class of scholars and bureaucrats. The region's rapid rise as an economic and political centre was, however, also the key to its undoing. The sudden spike in population density, and the intensive logging carried out for ceramic production, and temple and ship building, overtaxed the area's natural resources. The burden on the local ecology was exacerbated by the TrâÌn dynasty's dyke building project, which shifted the river's course. The ensuing environmental deterioration might have been one major reason for the Vietnamese forsaking the large-scale ceramic production in Chu âòu, deserting their main port, Vân ôÌn, and for the Chinese abandoning a historical maritime invasion route.