As construction of the National Road approached Preble County in 1830, local economic expectations rose, and county surveyor John Mumma bought 158 acres of farmland for $7,900 and laid out the town of Euphemia along the proposed route in May 1839. On the first day’s sale, October 1, 1839, ten village lots were sold. Euphemia quickly became a boom town with three taverns, dry goods stores, three blacksmiths, carriage shops, a clothing store, and its own post office, while new brick housing gave the community a more modern and prosperous appearance than timber buildings. Its fortunes later declined when the Dayton Turnpike diverted traffic from the National Road, and while residents succeeded in getting the road completed to the state line despite its remaining unimproved in western Ohio, neighboring Lewisburg gained the railroad and annexed Euphemia in 1916.