someone who opposed to slavery

carpetbagger
planter
abalonists
scalawag

Carpetbagger: A carpetbagger referred to a person from the Northern states who went to the South after the American Civil War, aiming to profit from the chaotic aftermath by taking advantage of the region's economic and political instability. While not specifically opposed to slavery, many carpetbaggers were against the institution and supported civil rights for African Americans.

Planter: Planters were large-scale landowners in the Southern United States who owned and operated plantations, usually growing cash crops such as cotton, tobacco, or rice. While some planters supported slavery due to its economic benefits, not all planters were in favor of the institution. There were planters who opposed slavery for moral, religious, or political reasons and advocated for its abolition.

Abolitionists: Abolitionists were individuals who actively opposed and sought to eradicate slavery. They were engaged in various activities such as protests, writing, and organizing movements to raise awareness about the immorality and injustice of slavery. Prominent abolitionists include Frederick Douglass, Harriet Tubman, and William Lloyd Garrison.

Scalawag: The term "scalawag" was used during the Reconstruction Era in the United States to describe white Southerners who were accused of being traitors to their region and their race. Many scalawags were former Confederate supporters or ex-Confederate soldiers who rejected the ideals of the Confederacy after the Civil War. While not necessarily opposed to slavery, some scalawags supported the goals of the Reconstruction Era, including civil rights for African Americans and the economic rebuilding of the South.