Public actors associated with the tradition of American antislavery constitutionalism in the nineteenth-century insisted that the Constitution of 1787 contained certain inbuilt purposes or animating principles, which ought to have aided constitutional interpreters in construing specific provisions of the constitutional text that related, directly or indirectly, to the law and politics of slavery in the United States. The Constitution of 1787 recognized the existence of slavery in the several states, yet antislavery constitutionalists interpreted even the slavery-related clauses as aspiring toward a certain liberal constitutional vision that was not yet a reality. In this dissertation, I argue, first, that these nineteenth-century interpretations of the Constitution in antislavery terms were intricately bound up with theories of natural law, and, second, I suggest that this aspect of the antislavery constitutional tradition offers a strong interpretive challenge (both descriptive and normative) to various aspects of the current scholarly literature on constitutional development and constitutional theory. / text