On August 14, 1848, Congress created the Oregon Territory, an area encompassing present-day Oregon, Idaho, Washington, and parts of western Montana and Wyoming. From the northern section of that land, the Washington Territory was created on March 2, 1853. Finally, on November 11, 1889, President Benjamin Harrison declared Washington the forty-second state in the Union.

This guide offers a selection of resources and strategies for Washington local history and genealogy research. These include the print and digital collections of the Library of Congress, as well as external repositories and web sites key to finding forebears in the Evergreen State.