in 1868, the 14th Amendment was ratified. This amendment grants citizenship to African Americans. More information on this Amendment is below:
http://www.americaslibrary.gov/jb/recon/jb_recon_revised_1.html
http://www.history.com/this-day-in-history/14th-amendment-adopted
https://www.loc.gov/rr/program/bib/ourdocs/14thamendment.html