Johnson City br/Blanco County, Texas br/30 16.657' N 98 24.688' W br/br/Text: Formed from Burnet, Hays, Gillespie and Comal counties. Created February 12, 1858, organized April 12, 1858. Named for the stream which traverses the region. County seat, Blanco City, 1858-1890; Johnson City, since.