Amendments 13, 14, 15
13th Amendment (1865)
Abolition of slavery: Slavery is not allowed in any state or territory under the govenment of the U.S.A.
14th Amendment (1868)
Civil Rights in the States; All persons born or naturalized in the United States are subject to its laws and cannot be denied any of the rights and priviledges contained in the Constitution.
15th Amendment (1870)
Black suffrage: Citizens cannot be denied their right to vote because of their race or color or because they were once slaves.