The 13th 14th and 15th Amendments to the US Constitution are often called the "Reconstruction Amendments" or the "Civil War Amendments."
13th Amendment: abolished slavery and involuntary servitude, except as punishment for a crime. It was ratified in 1865.
14th Amendment: granted citizenship to all persons born or naturalized in the United States, including former slaves, and guaranteed all citizens “equal protection of the laws.” It was ratified in 1868.
15th Amendment: prohibits the federal government and each state from denying a citizen the right to vote based on that citizen's "race, color, or previous condition of servitude." It was ratified in 1870.