Humans have lived in the Willamette River Basin for about 10,000 years, clustered for the most part around the river. Most of the Native American inhabitants were part of the Kalapuyan family, including the Calapooia, Luckiamute, and Yamhill tribes. The Clackamas tribe, part of the Chinook family, lived along the lower Willamette River below Willamette Falls.
The relatively mild climate, the abundance of natural resources, and homestead opportunities drew large numbers of Euro-American settlers to the Pacific Northwest starting in the early 1800s. With the Coast Range and the Cascades forming barriers that constrained east-west movement, major north-south transportation corridors developed in the Willamette River Valley. By 1990, about 2 million people lived in the Willamette River Basin, representing 68% of the total population of Oregon.