Mississippi formally ratifies the Thirteenth Amendment to the United States Constitution, becoming the last state to approve the abolition of slavery. The Thirteenth Amendment was officially ratified in 1865.

Mississippi is a state in the Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the southwest, and Arkansas to the northwest. Mississippi's western boundary is largely defined by the Mississippi River, or its historical course. Mississippi is the 32nd largest by area and 35th-most populous of the 50 U.S. states and has the lowest per-capita income. Jackson is both the state's capital and largest city. Greater Jackson is the state's most populous metropolitan area, with a population of 591,978 in 2020. Other major cities include Gulfport, Southaven, Hattiesburg, Biloxi, Olive Branch, Tupelo, Meridian, and Greenville.

The Thirteenth Amendment to the United States Constitution abolished slavery and involuntary servitude, except as punishment for a crime. The amendment was passed by the Senate on April 8, 1864, by the House of Representatives on January 31, 1865, and ratified by the required 27 of the then 36 states on December 6, 1865, and proclaimed on December 18, 1865. It was the first of the three Reconstruction Amendments adopted following the American Civil War.

Slavery is the ownership of a person as property, especially in regards to their labour. It is an economic phenomenon and its history resides in economic history. Slavery typically involves compulsory work, with the slave's location of work and residence dictated by the party that holds them in bondage. Enslavement is the placement of a person into slavery, and the person is called a slave or an enslaved person.

March 16 is the 75th day of the year in the Gregorian calendar; 290 days remain until the end of the year.