Pacific islands such as Japan are often unduly represented as isolated places. Land-centric biases in fact obscure the ocean’s significance as an ecological connector and a catalyst of historical change. With prolific upwellings, seasonal winds, and fluctuating fishing grounds, the ocean consists of places and depths that attracted human interest at different times. An archipelago awash in nutrient-rich currents, Japan found itself amidst a contested frontier when international whalers in the 1820s ushered in competition over resources, islands, and dominion. To understand technology-driven expansion in its ecological dimension, historians need to adopt a volumetric understanding of the ocean. Analysing this process based on currents, migration routes and catchment areas brings transformations to the fore that are otherwise left out of context. It also helps dissect the economic and ideological structures that keep expanding resource frontiers vertically in the 21st century, towards ever-deeper deposits of fossil fuels and rare earth minerals.
