In June 1920, in Duluth, Minnesota, a mob of over 10,000 convened upon the police station, inflamed by the rumor that black circus workers had raped a white teenage girl--charges that would later be proven false. Three men were dragged from their cells and lynched in front of the cheering crowd.
More than eighty years later, Warren Read--a fourth-grade teacher, devoted partner, and father to three boys--plugged his mother's maiden name into...