In 1929, Tom Johnson and Harry Jackson arrived in Birmingham, Alabama to set up the Southern district of the Communist Party USA (CPUSA). District 17, as it would come to be known, had been tasked with a specific goal: support the self-determination of African Americans in the so-called Black Belt — a region made up primarily of freed slaves and their descendents stretching from Mississippi through Alabama to Georgia — by helping them form their own nation.

Although Johnson and Jackson were experienced organizers, the pair of white Northerners could not have anticipated what awaited them in Birmingham. White Southerners attacked them with the police and vigilante mobs. Black Southerners could not see how Black Belt self-determination was different from the segregation they already toiled under. Johnson left Birmingham in 1931, after police abducted, stripped, beat, and threatened to kill him. Jackson departed the following year, after suffering much the same.

Nevertheless, District 17 carried on. Abandoning their dreams of a Black Belt Republic, organizers focused on helping black Southerners defend themselves against day-to-day exploitation and violence. They assisted black sharecroppers struggling to unionize against their white landlords and fought the racist brutality of the criminal justice system. Most famously, District 17 led the defense of the Scottsboro Boys, nine black teenagers who were falsely accused of raping two white women. By the mid-1930s, the majority of the Alabama Communist Party was black.