1811 - John Jacob Astor establishes Fort Astoria on the Columbia
Hoping to establish robust trade relations with the native people of the Pacific Northwest and Asia, Astor dispatched expeditions by sea and land to reach the mouth of the Columbia. Those who arrived by sea in 1811 founded the town of Astoria and built a fort and trading post as a principal base of operations.
(for more on Astor and the fur trade, click here)
They were joined in 1812 by the party that made its way over land. To get there, the half starved Astorians, opened the route across the Blue Mountains to the Columbia at Umatilla, a route that thirty years later would become the final leg of the famed Oregon Trail.
Astor's venture failed in Astoria, and the resident partners sold out to the North West Company the following year. The British now had a foothold in Oregon, and they renamed Astoria, Fort George, and carried on the fur trade in Oregon until it merged with the Hudson's Bay Company in 1821.
Britain and the US agreed in 1818 that they would jointly occupy the vast territory originally comprising Oregon, Washington, and parts of Wyoming, Idaho, Montana and British Columbia - with an eye to dividing it equitably in some future time. That time didn't come until John Quincy Adams negotiated a treaty with England settling the line of demarcation at the 49th parallel.
Portrait by Gilbert Stuart