Abstract: In 1869, Mississippi voters ratified a radical new constitution that eliminated distinctions of race, including in its provision formalizing the unions of cohabiting couples as legal common law marriages at the time of ratification. Although white men had long established relationships of concubinage with Black women, the new constitution made it possible for interracial couples to claim the status of legal families. This article examines how Black women and their biracial children employed the 1869 state constitution to situate themselves as legal wives and legitimate children and the lawful heirs of dead white men. In response, white supremacists sought to deny them legitimacy by casting all relationships between Black women and white men as forms of concubinage that could never constitute legal marriages. This article examines how judges used the classification of concubine to distinguish Black common-law wives from white ones, undermining the radicalism of the new state constitution. By making it more difficult for Black widows and children to claim to be the rightful heirs of white men, the courts channeled inheritances toward more distant white relatives.