Dr Ranjan Batra, associate professor of neurobiology and anatomical sciences at the University of Mississippi Medical Center, saw the Steven Spielberg film "Lincoln", last November, and wondered afterward what happened when the states voted on ratification.
That night, Batra, who became a US citizen in 2008, went on the usconstitution.net website, learning the rest of the story. After Congress voted for the 13th Amendment in Jan 1864, the measure went to the states for ratification.
On Dec 6, 1865, the amendment received the three-fourths' vote it needed when Georgia became the 27th state to ratify it. States that rejected the measure included Delaware, Kentucky, New Jersey and Mississippi.
In the months and years that followed, states continued to ratify the amendment, including those that had initially rejected it. New Jersey ratified the amendment in 1866, Delaware in 1901 and Kentucky in 1976.
But there was an asterisk beside Mississippi. A note read, "Mississippi ratified the amendment in 1995, but because the state never officially notified the US Archivist, the ratification is not official".
The next day, Batra spoke with Ken Sullivan, an anatomical material specialist for UMC's body donation programme, The Clarion Ledger, a state newspaper, reported.
When Batra mentioned Mississippi had never ratified the amendment, Sullivan responded that he remembered state lawmakers had voted to ratify the amendment in 1995, when he was a senior at Crystal Springs High School.
Batra shared what he had read online, and Sullivan started researching. He telephoned the National Archives' Office of the Federal Register, confirmed Mississippi had yet to officially ratify the amendment and found out what paperwork was needed.
The Federal Register wrote back on Feb 7 to confirm that "with this action, the State of Mississippi has ratified the 13th Amendment to the Constitution of the United States."