The leader of the American anti-slavery movement known for his speeches and writings was Frederick Douglass. Born into slavery, Douglass escaped and became a prominent abolitionist, orator, writer, and social reformer. His powerful speeches and autobiographies, notably "Narrative of the Life of Frederick Douglass, an American Slave," highlighted the injustices of slavery and advocated for the rights of African Americans. Douglass’s eloquence and determination helped to galvanize public opinion against slavery, making him a central figure in the fight for emancipation and civil rights in the 19th century.