Eric Foner has observed that historians of the Thirteenth Amendment have struggled “to find ways to get the voice of African Americans into discussions of the Amendment’s original meaning, scope, and limitation.” This article is part of a project to answer Professor Foner’s challenge to recover nineteenth-century African American constitutionalism. While there are many sources for accessing the views of African American writers, speakers, and activists, this article focuses on the rich contributions of the Black Convention Movement. Despite its importance in helping to set the terms for Reconstruction, the Black Convention Movement and the Black public sphere more generally have been under-utilized and under-studied as a part of our constitutional history. The documents from the state and national conventions of African Americans that took place from 1831 through the 1860s provide evidence of how African Americans understood constitutional ideals, principles, interpretations, and text in the period of time when significant constitutional change was about to take place. As we will see, the conventions included debates and statements about a range of constitutional ideas, from the meaning of freedom in a society infused with slavery and race prejudice, to complex views about the meaning of national citizenship, to fundamental questions about the validity and morality of the constitution itself.By the 1860s, as the Civil War revealed the possibility of an America freed from slavery, African American Conventions began to present a broad vision of civil society where constitutionally protected freedom and citizenship encompassed everything from suffrage to employment to property to education. This vision, while shared intermittently by some white abolitionist allies, was both more insistent and more encompassing than those ideas of freedom most often articulated in the white public sphere. This vision, I argue, is the lost meaning of African American constitutionalism and is one well worth exploring as we consider how and whether American constitutionalism in the twenty-first century can speak to us