Coeur d'Alene Miners Strike Violence Triggers Martial Law, 600 Imprisoned Without Trial

Violent confrontation erupts between striking silver and lead miners and company guards at mines in Coeur d’Alene, Idaho, after union workers discover a Pinkerton agent has infiltrated their organization and routinely provided confidential union information to mine owners. The violence follows months of labor tensions triggered by mine operators installing steam-powered drilling machines that increase low-skilled jobs like shoveling while eliminating highly skilled hand-drill miner positions. On the night of July 10, armed union miners gather on hills above the Frisco mine as reinforcements arrive from surrounding communities. At five in the morning of July 11, sustained gunfire breaks out—with each side claiming the other fired first—and the conflict escalates throughout the day. Union miners dynamite a mill during the battle, which ultimately leaves six people dead and dozens wounded.

Governor N.B. Willey requests federal military intervention, and President Benjamin Harrison dispatches General J.M. Schofield with federal troops who declare martial law and arrest 600 striking miners. The military holds the arrested workers in unsanitary stockade prisons—dubbed “bull pens”—without hearings, formal charges, trial, bail, or notice of accusations against them, in flagrant violation of constitutional rights. The military occupation pursues an explicitly pro-management course: removing local officials sympathetic to strikers, arresting over 300 union members for indefinite detention, closing down the union commissary, and protecting imported strikebreakers. Martial law continues for four months until Governor Willey finally lifts it on November 19, 1892, after the strike is comprehensively broken.

General Schofield orders local mine owners to discharge any union members they had rehired, cementing corporate control and eliminating union presence from the mines. The catastrophic defeat and brutal military response become the primary motivation for miners to establish the Western Federation of Miners (WFM) on May 15, 1893, in Butte, Montana, as a direct result of their Coeur d’Alene experiences. The Coeur d’Alene strike establishes a template of corporate espionage using Pinkerton infiltrators, federal military intervention on behalf of mine owners, suspension of constitutional rights through martial law, and mass imprisonment of workers without due process—patterns replicated at Homestead (1892), Pullman (1894), Cripple Creek (1903-1904), and Ludlow (1914) as standard operating procedure for crushing labor organizing in extractive industries throughout the Gilded Age and Progressive Era.