The correct answer to this open question is the following.
The top five list of the most impactful changes to the African American population would be the following.
1.- The Emancipation Proclamation. of September 22, 1862
The United States President Abraham Lincoln issues the Emancipation stating that will be valid until July 1863.
2.- The 13th Amendment to the United States Constitution that prohibits slavery
3.- The 14th Amendment to the United States Constitution guarantees all people, including African American former slaves, the protection of the law in the US.
4.- The 15th Amendment to the United States Constitution allowed African American men to vote.
5.- The 19th Amendment of the United States Constitution allowed women to vote, including black women.
All of these were important pieces of legislation that were aimed to improve the quality of life of African Americans in general. although we know that life in the South for black people continued to be very difficult after the Reconstruction years with the surge of the Ku Klux Klan, the Jim Crow laws, and the black codes.