Gold was discovered here in 1866 by William Wilson.  By summer, the area was saturated with prospectors.  The town site was originally named Wilsonville, but was changed to Pine Grove in 1868.  By this time the townsite had a post office, the weekly News, and a population of around 200.  Two steam-powered stamp mills and three arrastras treated both gold and silver ores.  Supplies were brought in by freight lines from as far away as Sacramento California.

By the early 1870s the population had swelled to 600, and the town was comprised of five saloons, three hotels, general stores, hardware store, Wells Fargo agent, dance hall, blacksmith shops, barber shops, school, livery stables, and two doctor’s offices. There were two large mines, the Wilson Mine and the Wheeler Mine.  By 1893, these two mills produced $8 million in bullion.  After the demonetization of silver in 1893, the Pine Grove mines were only worked intermittenly.