Many of these maps were surveyed for the railroads after the Civil War. The State of Texas traded the various railroad companies alternating tracts in each county in exchange for their commitment to bring rail tracks through each state. The transactions were motivated by the need to develop transportation for farm and ranch production to market. When the railroads ended up owning all the rural land they consequently owned substantial mineral rights. The Texas Railroad Commission was established to regulate the railroads and subsequently it regulated the oil and gas business since the railroad companies owned all the minerals. The Commission still regulates the energy business in Texas.