(1862–76) Secret organization of U.S. coal miners in Pennsylvania and West Virginia.
To protest poor working conditions and employment discrimination in the 1860s, the Irish-American miners formed a group named for an Irish widow who had led antilandlord agitators in Ireland. Acts of sabotage and terrorist murders in the coalfields were blamed on the group, and mine owners hired a Pinkerton detective, James McParlan, to infiltrate the organization. Based on his testimony in the widely publicized trials (1875–77), 10 "Mollies" were convicted of murder and hanged.