The purpose of these three Amendments of the Constitution was to give rights to African Americans. The 13th Amendment banned Slavery. The 14th Amendment protected the rights of citizens against interference by the State. And finally, the 15th Amendment established that men of any color and any race have the right to vote. | The purpose of these three Amendments of the Constitution was to give rights to African Americans. The 13th Amendment banned Slavery. The 14th Amendment protected the rights of citizens against interference by the State. And finally, the 15th Amendment established that men of any color and any race have the right to vote. |