Montana Vigilantes

The history of vigilante justice and the Montana Vigilantes began in 1863 in what was at the time a remote part of eastern Idaho Territory. Vigilante activities continued, although somewhat sporadically, through the Montana Territorial period until the territory became the state of Montana on November 8, 1889. Vigilantism arose because territorial law enforcement and the courts had very little power in the remote mining camps during the territorial period.

In 1863–1864, Montana Vigilantes followed the model of the San Francisco Committee of Vigilance that existed in 1850s California to bring order to lawless communities in and around the gold fields of Alder Gulch and Grasshopper Creek. There are estimates that over 100 persons were killed in "road agent" robberies in the fall of 1863. The Vigilance Committee of Alder Gulch organized in December 1863, and in the first six weeks of 1864 at least 20 road agents of the infamous Plummer gang, known as the "Innocents", were captured and hanged by the organization. Formal territorial law reached Alder Gulch in late 1864 with the arrival of Territorial Judge Hezekiah L. Hosmer and vigilante activity ceased in the region.

As the gold fields of Alder Gulch and Grasshopper Creek declined in 1865, prospectors and fortune seekers migrated to newly discovered areas in and around Last Chance Gulch (now Helena, Montana). As lawlessness increased, vigilante justice continued there with the formation of the Committee of Safety in 1865. During the period 1865–1870, at least 14 alleged criminals were executed by Helena's vigilantes. In 1884, ranchers in Central and Eastern Montana resorted to vigilante justice to deal with cattle rustlers and horse thieves. The best-known vigilante group in that area were "Stuart's Stranglers", organized by Granville Stuart in the Musselshell region. As formal law enforcement became more prevalent in the region, vigilantism fell into decline.

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