Vigilantes from Mississippi seized another union member, Lula Black, and her four children from her house, knocked her down, pistol whipped and kicked her, then took her to jail. Carrying an ax with their guns, they then moved to another home, where they murdered yet another union member, Frances Hall. In a final act of disrespect, they tied her dress over her head and left her body on the side of the road for several days.

Seventy-nine-year-old Ed Coleman had remained at home with his wife when people fleeing Hoop Spur came to his house and warned them to leave. As they ran from the posse, the Colemans saw his neighbor, Jim Miller, and his family burned alive in their house. After hiding for two days in the woods, the Colemans returned home to find dead bodies of women and children scattered about their community.

Families of union members found no welcome when they returned to their homes. The wife of Frank Moore had hidden for four weeks. When she came back to her neighborhood, a plantation manager, Billy Archdale, told her “if she did not leave, he would kill her, burn her up, and no one would know where she was.” Most of those who survived found their homes emptied of possessions that appeared in white peoples’ homes.

Ms. Wells Barnett provided hard evidence of the massacre, but it took the Supreme Court to expose the truth to national attention. In Moore v. Dempsey, the court in 1923 overturned the convictions of six of the Elaine 12, arguing that the confessions had been secured through torture. The trial had occurred in a setting dominated by a mob spirit, violating the prisoners’ right to due process.

The decision by the justices was aided by two white men involved in the massacre who reversed their previous testimonies. They now verified that the planters had gone to the Hoop Spur church to destroy the union and that the posse had killed their own men, instead of the black people who had been accused. They described the wholesale massacre of hundreds of unarmed and defenseless black people, and the torture used to secure confessions. The murders, thefts, violence and terror continued long after the troops had gone and the convicted men had been released.

It is impossible to establish an accurate death toll. Military reports were intentionally vague. Local authorities blocked press coverage. Many denied the massacre had occurred, leaving accounts of the slaughter to witnesses, reports from Wells Barnett, and stories passed down through families of the victims. Estimates have ranged from 25 to 853, the latter from an Arkansas Gazette reporter who named no source. Walter White, of the N.A.A.C.P., reported first that more than 100 African-Americans were killed, later changing it to 250.

At least two historians, including myself, have settled on a reasonable estimate of 200, recognizing that the toll was most likely far greater. What is certain is that the massacre cast a long shadow for decades, with fear of reprisals silencing those who witnessed and survived the terror.