As the California gold rush slowed in the late 1840s, miners pushed north and east in search of new claims. Gold was discovered in southern Oregon in 1852 in the Rogue River drainage and, by 1854-55 on the Santiam River, a Willamette tributary, and east of the Cascades on the John Day River. A steady flow of humanity followed — more miners, shopkeepers, farmers, teamsters, and practically anyone else who thought the miners and the nascent mining industry offered a source of profit and, perhaps, riches.

As the Oregon diggings grew, miners pushed farther north, reporting significant strikes in eastern Washington Territory and southern British Columbia, particularly on the Fraser River, from 1858 into the early 1860s. Hudson’s Bay Company employees at Fort Colville, who were familiar with the gold-bearing sands of rivers in California, recognized gold in the sand of the Columbia River in 1852 but told only a few of their French Canadian associates in the Willamette Valley. These men hurried to the fort and began washing gold from the river shores. By 1855, the word of their discovery was out. Occasional groups of miners traveled across the newly established Yakima Indian reservation to reach Fort Colville, angering Indians who had signed treaties that year. The treaties promised that non-Indians would stay off the reservations, and the trespasses led to further hostilities. The U.S. Army closed eastern Washington Territory to further settlement in 1856 in response to war with the Yakamas, but miners were exempted, and small numbers of them, bravely or foolishly, continued to arrive. Wary of the hostilities, however, many pushed on to the comparatively richer and safer Fraser River district.

Missionaries and fur trappers had moved through the area, established settlements and, over a period of a few decades, done their work and moved on. The hostilities of the 1850s slowed, but didn’t halt, the flow of miners into the interior Columbia basin. The lure of gold was too strong. Miners came by wagon train from the east, and up the Columbia River via steamboats from the west. Cities grew up quickly around the gold strikes, places like Elk City, Idaho, on the South Fork Clearwater River east of Lewiston, where gold was discovered in 1860. Within a year the city had 1,500 residents. Many of these instant cities died just as quickly when the gold played out.

The gold rush to central Idaho and eastern Oregon between 1861 and 1870 is significant in Columbia River history, as it brought waves of people up the Columbia from the coast to try their luck and settle the interior. In 1861 alone, it was reported that 10,500 men came up the river. In 1863 the number was  22,000, and in 1864, 36,000. Boat traffic on the Columbia and Snake rivers increased significantly during this time, hauling freight and passengers to the mining districts. Two new steamboats were built above Celilo Falls to provide service between there and Wallula at the mouth of the Walla Walla River. Most of the passengers just wanted to reach the mining districts as quickly as possible, but some traveled in style. The boats could be quite opulent. For a price, passengers could enjoy champagne cocktails, Havana cigars and fresh-caught salmon in fancy shipboard dining rooms.

Soon the richest strikes were booming and the lesser locations were declining. By 1864 there were 10 major mining districts in Washington Territory, which at the time included present-day Idaho and western Montana. Walla Walla and The Dalles, initially overwhelmed by the influx of miners and associated entrepreneurs, became the focal points of the interior trade as the mass of humanity moved on to the interior. Both towns were strategically located on major trade routes and trails, and both prospered as a result. The Oregon Steam Navigation Company commanded river traffic from Portland to Fort Nez Perces, at Wallula, and the mining traffic provided a windfall. Some of the mining districts were fabulously successful. Between 1860 and 1900 placer mines in the Clearwater and Salmon river drainages yielded between $30 million and $60 million in gold.

Mining opened the interior Columbia River Basin to settlement The gold rushes of the 1860s spurred population growth, as many of the miners stayed to take up farming or ranching. By the end of the 1860s many of the boom towns that grew up around the mines had established themselves as communities of some permanence, and there was regularly scheduled transportation between them and the commerce centers of Walla Walla, The Dalles and Portland via stage coaches or steamboats. Orofino (“fine gold” in Spanish), Pierce (for Capt. E.D. Pierce, the first to discover gold in Idaho) and Wallace (for William Wallace, the first territorial governor), Idaho, all grew up around placer mines. The original name of Wallace, at the time the Colonel was supplying miners, was Placer City. Lode mines followed the placer mines. Noah Kellogg, for whom the Idaho city west of Wallace is named, discovered the deposits that were developed as the Bunker Hill and Sullivan silver mines, the richest mines in the Coeur d’Alene district and among the richest in the world.

The Old Dominion Mine near Colville, discovered in 1885, led to the development of that city and also helped Spokane prosper, as did the mines of the Coeur d’Alene district and, later, the Metaline district in the northeast corner of the state and British Columbia.