In Heart of Atlanta Motel v. United States (1964), the U.S. Supreme Court unanimously affirmed Congress’s power under the Commerce Clause to pass Title II, the public accommodations component of the Civil Rights Act of 1964 (CRA). The Johnson Administration expressed hope that this unanimous decision would aid the “reasonable and responsible acceptance” of the CRA. A less familiar legacy of this case is the role played by the Thirteenth Amendment and its declaration that “neither slavery and involuntary servitude . . . shall exist within the United States.” The owner of the Heart of Atlanta Motel unsuccessfully invoked this amendment to challenge Title II, drawing on a particular conception of private property. The Court rejected this argument briskly. Looking at this case in isolation would leave a modern reader ignorant of the role played by the Thirteenth Amendment in the debate over the enactment of Title II. This article revisits the Heart of Atlanta Motel case, drawing on contemporaneous press coverage and legal commentary about it and related legal challenges. It then shows how, when Congress considered Title II, proponents and opponents both appealed to the Thirteenth Amendment. The Administration and Congressional supporters emphasized the Commerce power as the constitutional hook for Title II, mindful of the Court’s invalidation, in the Civil Rights Cases (1883), of the Reconstruction-era public accommodations law of 1875 and of the fate of Thirteenth and Fourteenth Amendment arguments there. However, they appealed to the Thirteenth Amendment, in conjunction with the Fourteenth Amendment, and to the unfinished business of Reconstruction. The Thirteenth Amendment, they argued, sought to abolish all the incidents of slavery and to secure full citizenship; racial discrimination in public accommodations was a continuing badge of servitude. By contrast, opponents of Title II (e.g., Senator Strom Thurmond) argued that the Thirteenth Amendment forbade Title II; they equated “involuntary servitude” with “rendering involuntary service” and with violating private property rights. This claim returns in the Heart of Atlanta challenge and the rhetoric of fellow Atlanta restaurant owner (and, later, governor) Lester Maddox. The article concludes by examining the legacy of Heart of Atlanta Motel for later antidiscrimination laws and their critics, focusing on analogies between race discrimination and other forms of discrimination, such as sex and sexual orientation.