The Chinook people dominated the lower Columbia River and its estuary — one of the richest environments on the continent. They were master traders whose language became the basis for Chinook Jargon, the trade pidgin of the Pacific Northwest.
The expedition encountered the Chinook near the mouth of the Columbia in November 1805. Relations were generally cordial but sometimes tense, as the Chinook were experienced traders who drove hard bargains and the captains were frustrated by what they perceived as theft.
The Chinook economy was based on salmon, which they caught in enormous quantities and traded throughout the region. Their material culture — plank houses, ocean-going canoes, elaborate woodwork — impressed the expedition members, though Clark complained about fleas in the Chinook dwellings.
The Chinook, like many Pacific Northwest peoples, suffered catastrophic population decline in the early 19th century from introduced diseases, particularly the malaria epidemics of the 1830s.
