The Portland area was long home to Native Americans. Chinook peoples concentrated on lowlands along the Columbia River, such as Sauvie Island, where it was easy to harvest fish, birds, and wild plants. A second center for native peoples was below the falls on the Willamette River, near present-day Oregon City. The Tualatin Valley (in what is now Washington County) was home to groups of the Kalapooia people who depended heavily on wild game. Measles and malaria, introduced by nonnatives in the early 1800s, killed most of the native peoples because they lacked natural immunities to these diseases.
Although Fort Vancouver was established on the Washington side of the Columbia River in 1825 and settlers traveling the Oregon Trail began reaching the Willamette Valley in the early 1840s, Portland's beginnings as an English-speaking community date to 1845. Initial growth was based on the sale of lumber and grain to California during the gold rush of the 1850s. Discovery of gold around the headwaters of the Columbia River in the 1860s further expanded the city's importance as a river port.
