Portland (Or.).

Portland, Oregon, began as a clearing on the west bank of the Willamette River in 1844. The new city was incorporated in 1851 and prospered because of its advantageous location near the confluence of the Willamette and Columbia Rivers, among other factors. Its growth was spurred by flourishing agriculture in the Willamette Valley, the California gold rush, the Indian wars of the 1850s, and gold discoveries in eastern Oregon and Idaho in the 1860s. By the Civil War, Portland was the principal metropolis of the Pacific Northwest with a population of around 3000. The arrival of the Northern Pacific and Union Pacific railroads in 1883 and 1884 contributed to a new boom in prosperity, and in 1891 the city annexed the municipalities of Albina and East Portland on the east side of the Willamette. Residential growth was most dramatic in the eastern districts after 1900, and expansion was especially rapid after the Lewis and Clark Centennial Exposition in 1905. By 1910 Portland's population was over 207,000, and it continued its rapid growth up to the 1930s.