Blumenthal is an unincorporated farming and ranching community on the Pedernales River in Gillespie County, in the U.S. state of Texas. It is located halfway between Fredericksburg and Stonewall on U.S. Highway 290, approximately at the intersection of Jung Lane. The community was believed to have been settled about 1900, and reached its peak population of twenty-five in 1945.Nearby businesses are a bed and breakfast concern, and Wildseed Farms.