Southern sympathizers settled in Buena Vista Canyon in 1861 after the discovery of silver ore. Appropriately called Dixie, their camp's name changed to Unionville in late 1861, when the will of the neutral and Northern factions of the population prevailed. The town was designated as the seat of Humboldt County, which was itself the product of Buena Vista mining activity. Unionville lost this distinction to Winnemucca in 1873.

By the late 1870's, most of the local ores were depleted, but it has remained a pleasant place, enjoying more amenities and less violence than most mining towns in spite of strong political feelings.

Today, Unionville still retains its picturesqueness.