Fort William ( Oregon ) Fort William was a fur trading outpost built in 1834 by the American Nathaniel Jarvis Wyeth , a mountain man , backed by American investors . It was located on the Columbia River on Wappatoo Island in what is now part of Portland , Oregon . After a few years , in 1837 Wyeth leased the post to the British Hudson ’ s Bay Company , which had much more power in the region from its base at Fort Vancouver on the Columbia River near the ocean . In 1835 the fort settlement was the site of a murder and the first Euro - American trial to be held in what is now the state of Oregon . Background . The fort was built by Wyeth and his company as part of the Pacific Trading Company , a joint - stock company formed by Wyeth to exploit the fur trade in the Oregon Country . Henry Hall of Boston ' s xx He also held Fort Hall in southeastern Idaho , to take advantage of trade in the Rocky Mountain region . His intention was to establish a fishery at Fort William , and export salmon to the East and Hawaii . The island chosen was previously visited by the Lewis & Clark Expedition , and was previously inhabited by Native Americans . By the time Wyeth established his outpost , the island was void of any human habitation due to epidemics of infectious diseases that had swept through the lower Columbia region . As the Natives did not have any immunity to the new Eurasian diseases , nearly 90 % of them died from smallpox , measles and other illnesses following European contact . Location . Wappatoo Island , now Sauvie Island , lies just north of the main confluence of the Willamette and Columbia Rivers . The north end of the island is at the confluence with the Multnomah Channel . The post was built on the north end of the island , but was moved the next year toward the center of the island due to seasonal flooding . Fort William was west of and on the opposite side of the river from the Hudson ’ s Bay Company ’ s ( HBC ) Fort Vancouver , established in 1824 on the north side of the Columbia . It was about upriver from the mouth of the Columbia and the HBC post of Fort George ( formerly Fort Astoria ) . Operation . Wyeth and crew attempted various commercial interests from their outpost in the Pacific Northwest . They cut lumber and exported it to the Hawaiian Islands , built boats and canoes , and built a - long building to use in processing fish . They intended to ship salmon to the East and to Hawaii . Wyeth and his employees also attempted to trap animals in the Deschutes River watershed of central Oregon . They were unsuccessful and the young company was unable to survive against the HBC and , in the Rocky Mountains , the American Fur Company , made a monopoly by John Jacob Astor . John Ball , one of Wyeth ' s men , wrote that they were no match for the HBC , which up fur trade prices as much as ten to one whenever any American trader appeared on the lower Columbia River . The post had difficulties ; its first supply ship sent to the Northwest Coast wrecked , and the second ship was late . The first ship was being used to export salmon . Wyeth abandoned the post in 1836 and the following year , leased it to the Hudson ’ s Bay Company . After Wyeth left the Pacific Northwest , John McLoughlin , the Chief Factor at Fort Vancouver , ordered Fort William demolished and a dairy farm built on the island . Wyeth also sold Fort Hall in present - day Idaho to the HBC the following year . Murder . Fort William was the site of the first public trial by European Americans in Oregon . In 1835 , the post ’ s gunsmith , Thomas J . Hubbard , attacked and killed the fort ’ s tailor in an argument over a young Native girl . The naturalist John Kirk Townsend was appointed magistrate , although he was a friend of Hubbard ' s . The jury acquitted Hubbard when they ruled the death was justifiable homicide . This verdict was likely the result of evidence that the tailor had alcohol - induced rages .