The abolitionist movement played a critical role in U.S. history by advocating for the end of slavery and promoting the rights of African Americans. Emerging in the early 19th century, this movement included a coalition of both Black and white activists who sought to expose the moral and humanitarian crises associated with enslaved labor. Key figures like Frederick Douglass and Harriet Tubman pushed for legal reforms and public awareness. The efforts of abolitionists culminated in significant legal changes, including the Emancipation Proclamation and the eventual passage of the 13th Amendment, which abolished slavery in the United States.