[2] The county was named in honor of the United States President George Washington.

[3] At the 2000 census there were 4,926 people in 1,989 households, including 1,408 families, in the county.

Like all of the High Plains, Washington is a powerfully Republican county in Presidential elections.

Among Colorado counties only Washington, Elbert and Hinsdale were carried by Barry Goldwater in 1964, and no Democratic presidential nominee has carried Washington County since Franklin Delano Roosevelt in 1936.

The last five Republican presidential candidates have all obtained over 75 percent of Washington County's vote.

In other statewide elections, Washington County also leans Republican, although the county was carried by Democrat Roy Romer by a narrow margin in 1990[11] – when he carried all but three counties statewide – by Dick Lamm in 1982[12] and by Constitution Party candidate Tom Tancredo in 2010.