Washington County is a county located in the U.S. state of Vermont, named after George Washington. As of the 2010 census, the population was 59,534, making it the third-most populous county in Vermont, but the second-least populous capital county in the nation, after Hughes County, South Dakota. Its shire town is Montpelier, the state capital. The county was created in 1810 as Jefferson County and organized the following year.