Established in 1864 as a mining camp in the northern Rocky Mountains on the Continental Divide, Butte experienced rapid development in the late-nineteenth century, and was Montana's first major industrial city.[4] In its heyday between the late-nineteenth and early-twentieth centuries, it was one of the largest copper boomtowns in the American West. Employment opportunities in the mines attracted surges of Asian and European immigrants, particularly the Irish;[5] as of 2017, Butte has the largest population of Irish Americans per capita of any city in the United States.[6]

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