Union, the county seat of Monroe County, is located in rolling limestone farm country at the intersection of U.S. 219 and State Route 3. The town, at an elevation of 2,071 feet, had a population of 427 in 2020.

Union is an old community, settled by James Alexander in 1774. Alexander later donated acreage for the town and additional land for nearby Green Hill Cemetery. Union was established by the Virginia legislature in 1800 to be the seat of government for newly established Monroe County. Some objected that the location was not central to the county, which was originally larger than it is today. Several frontier forts were located in the region, and the town received its name because it was a place where militia united for common drill during the Indian wars.

Ironically, considering its name, the people of Union and the surrounding area generally sided with the South during the Civil War. Today, Union is noted for the presence of the statue of a Confederate soldier, which stands alone in a field just outside town. The first Monroe County courthouse, built of logs, was replaced by a brick structure in 1820. The current courthouse was built in 1881. Elmwood, the ancestral home of the Caperton family, is among several historic houses in the Union area.