The county was formed in 1858 from parts of Russell and Tazewell counties. It was named for James Buchanan, the 15th President of the United States. In 1876, Grundy was chosen and designated by the legislature as the county seat of Buchanan County, it was named in honor of Felix Grundy, a United States Senator from Tennessee.
In 1880, the southwestern part of Buchanan County was combined with parts of Russell and Wise counties to become Dickenson County.
Helen Timmons Henderson (1877–1925) participated in the work of the Buchanan Mission School at Council, Virginia. She and Sarah Lee Fain (1888–1962) of Norfolk were the first two women to be elected to the Virginia General Assembly. They were both Democrats in the House of Delegates. When Henderson was in office, delegates approved construction of 6.2 miles (10.0 km) of improved road to be built from Russell County, across Big "A" Mountain, to Council. What is now Route 80 is also known as "Helen Henderson Highway".
This project is a table of contents for all projects relating to this County of Virginia. Please feel free to add profiles of anyone who was born, lived or died in this county.