Swan Island is located on the Willamette River about 4.5 miles (7.2 km) downriver from downtown Portland, Oregon, United States.

[3][4] River traffic on the Willamette was impeded by a bar near the island, and annual dredging by the U.S. Army Corps of Engineers was required to maintain a navigable channel.

[5] A 1914 Oregonian article reported that the Portland Commission of Public Docks was unanimously in favor of removing the island, instead of developing it for commerce.

Portland did not have an airport at the time, and air mail was instead flown to Pearson Field in Vancouver, Washington, about 10 miles (16 km) distant.

[18][19] Tenants of the Swan Island airport were ordered to leave the facilities in late February 1942 to make way for a U.S. Maritime Commission shipyard.

[20] The Swan Island Shipyard was one of seven constructed by industrialist Henry J. Kaiser on the West Coast—three in the Portland–Vancouver area and four in Richmond, California—to help meet the production demands of the U.S. Maritime Commission in World War II.

[24][25] After the conclusion of World War II, there was some dispute about whether Swan Island should continue to be used as an industrial area or re-appropriated for aviation purposes.