Final answer:
The Pacific Northwest was explored by Russia, Britain, Spain, and the United States. They were primarily seeking territorial expansion, fur trade, and a possible Northwest Passage to Asia. These explorations had significant impacts on the history and demographics of the Pacific Northwest.
Step-by-step explanation:
The nations that explored the Pacific Northwest include Russia, Britain, Spain, and the United States. They explored this region with numerous purposes in mind, including to extend their territories, for valuable fur trade especially otter and beavers, and to discover a potential Northwest Passage.
For instance, Spanish explorers sought to establish their control and protect their coastal territories from the potential British and Russian incursions. Similarly, British explorers were influenced by the prospects of finding the fabled Northwest Passage, a direct navigational route to Asia, as well as participate in the lucrative fur trade. The Russians explored the Pacific Northwest in part due to the fur trade as well, especially the sea otter trade, while the U.S. was driven by westward expansion and the doctrine of Manifest Destiny that proclaimed the country's divine right to span from Atlantic to Pacific.
Each nation sent various exploratory expeditions throughout the late 18th and early 19th centuries that profoundly shaped the history and the demographic composition of the region.
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