The “Railroad Commission of Texas” conjures up visions of oil and gas and power politics and perhaps the question, What does “railroad” have to do with petroleum? The Railroad Commission (RCT) also brings to mind modern America between 1930 and the 1970s, when the Texas agency controlled from 35 to 45 percent of the oil and gas produced in the United States. These images come from cultural myths of the Lone Star State, from Americans' fascination with conspiracies, and, most telling, from the lack of historical analyses of the commission, its staff, and its regulatory strategies. The prevailing views of the commission are unfortunate ones, for they not only neglect the agency's regulation of railroads, natural-gas utilities, and buses and trucks but also skew the understanding of how the state commission came to regulate petroleum in the first place, how it devised policies for doing so, and how it legitimized itself and defended that legitimacy under the weight of the East Texas crisis between 1930 and 1935.