The beginnings of La Plata can be traced back to March 17,1827 when Drury Davis established a trading post near the town's current location. The ensuing few years saw Davis joined by family and friends to ceate a small village that included a blacksmith shop, inn, and stagecoach station.
La Plata was platted in 1855. It was named after the city of La Plata, in Argentina. The name is of Spanish origin meaning "Silver". Two men, Louis Gex and Thomas Saunders, were the primary force behind the town's platting, and drew straws to choose the community's name. Saunders wanted to name the town Charlottesville to honor a favorite sister, while Gex pushed for the name La Plata. The North Missouri (later known as the Wabash Railroad) came to town in 1867, and the Santa Fe Railroad twenty years later, passing through La Plata on its route from Chicago to Kansas City. The combination of the the two railroads made La Plata an ideal shipping point for timber, livestock, grains, and other goods for northern Macon county and southern portions of neighboring Adair county as well.