Forsyth County, Georgia, at the turn of the twentieth century was home to a large African American community that included ministers and teachers, farmers and field hands, tradesmen, servants, and children. Many black residents were poor sharecroppers, but others owned their own farms and the land on which they'd founded the county's thriving black churches.

But then in September of 1912, three young black laborers were accused of raping and murdering a white girl. One man was dragged from a jail cell and lynched on the town square, two teenagers were hung after a one-day trial, and...