After the independence in America, slavery was considered illegal in the North as they were influenced by the ideas of John Locke that considered all men to be equal and free. The emancipation society in the North wanted to get over the system of slavery. The white Southerners succeeded in strengthening the institution.
Before the Civil War, the North continued to show their disinterest in the practice of slavery while the South continued to support it as it was part of their economy. Several compromises and laws were implemented to keep intact the slavery practices to expand in new territories.
After the Civil War, The South despite being losing the war tried to restrict the movement of African American as they were now freed. The KKK establish to terrorise the blacks. Segregation laws were implemented like Jim Crow Law.
African Americans had new employment opportunities as men went away to fight in the war. However, they still had to fight for civil rights, as seen by leaders like MLK or Malcom X.
Naturalization is the legal act or process by which a non-citizen of a country may acquire citizenship or nationality of that country. It may be done automatically by a statute, i.e., without any effort on the part of the individual, or it may involve an application or a motion and approval by legal authorities.