In the tumultuous decades after the Civil War, as the southern white elite reclaimed power, “racial mixing” was the central concern of segregationists who strove to maintain “racial purity.” Segregation—and race itself—was based on the idea that interracial sex posed a biological threat to the white race. In this groundbreaking study, Charles Robinson examines how white southerners enforced anti-miscegenation laws. His findings challenge conventional wisdom, documenting a pattern of selective prosecution under which interracial domestic relationships were punished even more harshly than transient sexual encounters. Robinson shows that the real crime was to suggest that black and white individuals might be equals, a notion which undermined the legitimacy of the economic, political, and social structure of white male supremacy. Robinson examines legal cases from across the South, considering both criminal prosecutions brought by states and civil disputes over marital and family assets. He also looks at U.S. Supreme Court decisions, debates in state legislatures, comments in the U.S. Congressional Record, and newspaper editorials. He not only shows the hardening of racial categories but assesses the attitudes of African Americans about anti-miscegenation laws and intermarriage. The epilogue concerns “The Demise of Anti-miscegenation Law” including the case of Richard and Mildred Loving. Dangerous Liaisons vividly documents the regulation of intimacy and its fundamental role in the construction of race.