This thesis examines the environmental history of the industrial transformation on the large lakes of Northwest Canada, Winnipeg, Athabasca, Great Slave, and Great Bear between 1921 and 1960. Using corporate and personal records, government documents, published scientific reports and oral history collections, it reconstructs patterns of industrial activity, relationships between these activities and local ecosystems, and environmental consequences. Touching on the history of the north, ecological colonization, the politics of resource development, and relationships between Natives and Newcomers the argument builds on two main threads of historiography: the place of industrial humans in nature and the role of twentieth-century science in shaping engagements with the natural world.

This study traces the development of mining, fishing, and transportation industries on the large lakes and their surrounding environment. This Subarctic development was a Canadian manifestation of international industrial transformations that sought increasingly remote resources for the production of goods destined to capitalist markets. I examined this transformation by asking what happens to nature (organisms, including humans, in relationship with their environment) as a result of twentieth-century industrialization (high-energy fuels, especially fossil fuels, and mechanical technologies applied to production)?

I argue that industrialization remained embedded in and dependent upon local ecosystems. Mining, elsewhere seen to exemplify the destructive and inorganic character of industry, integrated its operations with the physical world, extended habitable environments underground, and modelled its work on natural and human metabolism. Where ties to the physical world weakened in this period, it was as a direct result of the commodification of natural resources and how these were processed into goods for distant markets. Scientists played a major role in guiding industrial mining and fishing operations, with provincial and federal governments granting scientists authority to ensure fisheries conservation. The industrial transformation in this period carries the imprint of how these scientists imagined the natural world and the unintended consequences to lake ecosystems of these models.