“(Re)defining Radicalism: The Rise of Black Feminism and the Politics of Respectability, 1831-1895,” argues that nineteenth-century black feminists were progenitors of black radical thought because they advocated for black citizenship and self-determination. It further contends that black women actively subverted and negotiated the politics of respectability, or middle-class expectations of women’s proper behavior, in order to offer innovative arguments for black and women’s rights. “(Re)defining Radicalism” interrogates the speeches, published work, and correspondence of Maria Stewart, Sojourner Truth, Mary Ann Shadd Cary, Frances Harper, Ida B. Wells, and Anna Julia Cooper. Rather than reading these women strictly as writers and/or activists, I frame them as black radical theorists and position them as intellectuals who molded anti-racist and anti-sexist ideologies during the nineteenth century. Historians, Africana scholars, and feminist theorists have rightly framed nineteenth-century black women as key actors in the struggle to dismantle slavery and white supremacy. Yet, as they emphasize black women’s roles as doers, they often neglect their roles as thinkers. My dissertation instead seeks to re-center black women in the ideologies that they have created by illuminating their roles as black radical theorists. This research intervenes into scholarship on black women’s intellectual history by rejecting the dichotomy between respectability and radicalism. Some scholars describe the women in this study as conservative because of their class status and presumed respectability, which undermines their radical arguments and dismisses the complexity of their political thought. I instead demonstrate how respectability and radicalism function in tandem rather than in opposition to each other. This approach allows me to identify the strains of thought that unify seemingly disparate women who have previously been described as either conservative or militant. Thus, “(Re)defining Radicalism” offers an intellectual history that demonstrates how nineteenth-century black women thinkers were not isolated figures, but co-creators of a black feminist tradition.