This dissertation undertakes a historical examination of twentieth-century maritime Manchuria (Northeast China) to explore the role of seaborne interactions and coastal labor activities in shaping East Asian integration as well as social and environmental crises. "Maritime Manchuria" refers to the Bohai/Yellow Sea Rim, the area that runs along Manchuria, tracing the edge of east and north China and the Korean Peninsula, and extending into the corner of the Pacific. It is composed of port cities, less urbanized coastal villages, and the sea. The rim is not just a physical space, but also a space defined by social and economic relations. Questions animating this dissertation concern the kinds of human activities required to bring this rim into existence, the types of people who lived along the rim, and how they contributed to the development of the region.

The dissertation has two major goals: to highlight the transnational networks of commercial, cultural, and knowledge exchanges in the region, and to take full account of the everyday lives of local laborers, including male dock workers, women who grew seaweed and collected shellfish on shore, fishermen, students who were sent down to the coastal rural villages, and entrepreneurs. Its underlying argument is that region-making, nation-building, and environmental transformations require attention to those who made their living along the Manchurian coast. It shows the dialectic of transnationalism and modernity, which entailed the convergence of ideas, the circulation of commodities, and confrontations centered on labor displacement and marine environmental crises.