Most of Washington was built recently: 2% of its homes predate 1940 and the median home dates from 2010. Below: maps from 1893 on and the census since 1920.
While some sources list the town as having been named after George Washington, first president of the United States, the Encyclopedia of Oklahoma History and Culture relates a "popular local story" that the name was actually chosen to honor Caddo chief "Little Boy" George Washington, who had lived nearby.
A post office called Washington has been in operation since 1904. The post office charter was granted May 10, 1904.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021). How TownRatings grades history →
From Wikipedia, Wikidata and Wikipedia for famous people, U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the US Post Offices dataset (Blevins & Helbock) and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.