Bunker Hill and the Sullivan Mill Explosion

The Western Federation of Miners made several attempts to obtain better pay for their members working in the Bunker Hill and Sullivan Mine. When these failed, the union planned a demonstration in protest. The protest got out of hand and a train laden with explosives was hijacked and diverted to the mill where it was detonated, destroying the mill entirely.

In 1898 miners in the Silver Valley of northern Idaho struggled to secure better wages. Drill and powder men received $3.00 per day and “muckers” (shovellers) received $2.50 per day. Both wanted a fifty cent pay raise to bring them in line with the other mines in the area. However, with a supply glut in the silver market, margins were narrowing for mine operators and outside investors. To further their cause, many miners joined the Western Federation of Miners to collectively bargain for better wages.

Bunker Hill and Sullivan Mining and Concentrating Company, the largest mining company in the region, refused to even recognize the union or its members. They hired the Pinkerton Detective Agency and the Theil Detective Agency to send in spies pretending to be miners looking for work. These spies would then join the union and report back to Bunker Hill on the activities and membership of the unions. Bunker Hill was determined not to pay union wages and further reduce their profit margins. Local government leaders and businessmen urged Bunker Hill to pay the union scale and accused them of wanting to foment labor riots to discourage other outside investment when management refused to cooperate.

After fruitless attempts to obtain better pay for the union members, the Western Federation of Miners determined that a demonstration would be made against Bunker Hill on April 29, 1899. Although intended to be peaceful, the demonstration soon became violent. Union members in Burke, Idaho hijacked a train and rerouted it into Wardner, Idaho. Bunker Hill guards at Wardner exchanged gunfire with the union men. A large dynamite explosion destroyed the concentrator and seventy company offices as well as a cache of Springfield rifles belonging to the Army stored at the location. At least one union and one non-union worker died in the explosion.

Bunker Hill Mining had donated to several candidates for public office. Management used those political connections to call for help. On May 4, 1899, the governor of Idaho, Frank Steunenberg, declared martial law and asked for federal help. Black troops from Fort Sherman in Coeur d’Alene were sent into the area. Hastily constructed “bull pens” (makeshift jails) house those accused of participating in, or who were sympathetic to, the events of April 29. Troops also arrested the engineer of the hijacked train, the Populist sheriff, and two commissioners of Shoshone County. The arrest of the sheriff and commissioners led to their impeachment, which sent a message to other Populists not to support the miners.

The destruction of the concentrator mill delayed operations for three months. Bunker Hill built a new, more efficient concentrator to replace the destroyed one. Martial law lasted for two years. During that time, only those willing to forswear union membership were allowed to work in the Bunker Hill and Sullivan mine. What had started as an attempt to strengthen workers’ positions in relation to the company ended with the company stronger than ever.


Bull Pen, Kellog, ID
Bull Pen, Kellog, ID The "bull pen," a makeshift jail that held those suspected of involvement in the demolition of the concentrator and those openly sympathetic to them. Source: 8-X016, PG 8 Barnard-Stockbridge Collection, University of Idaho Library, Department of Special Collections and Archives. https://digital.lib.uidaho.edu/cdm/singleitem/collection/bar-stock/id/1033/rec/1
Bunker Hill, 1899
Bunker Hill, 1899 The Bunker Hill concentrator after the explosion of April 29, 1899 Source: 8-X014a, PG 8 Barnard-Stockbridge Collection, University of Idaho Library, Department of Special Collections and Archives. https://digital.lib.uidaho.edu/cdm/singleitem/collection/bar-stock/id/145/rec/4
Bunker Hill Rebuilt
Bunker Hill Rebuilt The new Bunker Hill concentrator. It took a mere 90 days to build and was more efficient than the previous one. Source: 8-X536, PG 8 Barnard-Stockbridge Collection, University of Idaho Library, Department of Special Collections and Archives. https://digital.lib.uidaho.edu/cdm/singleitem/collection/bar-stock/id/178/rec/7



Matt McCune, University of Idaho, “Bunker Hill and the Sullivan Mill Explosion,” Intermountain Histories, accessed April 14, 2024, https://www.intermountainhistories.org/items/show/118.