Mississippi

 Mississippi was a state of the United States of America.

The Eleventh Doctor, Alice Obiefune and John Jones visited Mississippi Delta in 1931. (COMIC: What He Wants...)

Elvis Presley was from a shack in Tupelo, Mississippi. (PROSE: That's All Right, Mama)

During a dream Benny once had, Mississippi was implied to be relevant to Martin Luther King, Jr. The dream involved a Dalek, a Cyberman, a Sontaran and Kadiatu Lethbridge-Stewart. During the course of it, Grinx the Sontaran said, "I have a dream that little Sontarans and little Rutans will one day walk through the streets of Mississippi, hand in tentacle..." (PROSE: The Also People)

Some time before 30 November 1955, Emmett Till's body was found in a river in Mississippi while on vacation from the north, after what was, according to Rosa Parks, a "couple words to a white woman". (TV: Rosa)

Behind the scenes
The state of Mississippi has received almost no attention in DWU fiction, not even in American Civil War stories like Blood and Hope. The river, however, is a more frequent topic of conversation.