The Copper Kings, industrialists William A. Clark, Marcus Daly, Mark Sloan, and F. Augustus Heinze, were collectively known for the epic battles they fought in Butte, Montana, and the surrounding region during the Gilded Age over the control of the local copper mining industry, a fight which had ramifications for not only Montana, but the United States as a whole.
The battles between Clark, Daly and Heinze, and later between just Heinze and industrialist financiers William Rockefeller and Henry H. Rogers are a large chapter in Montana history. Eventually, a company known as Anaconda Copper emerged as a monopoly, expanding into the fourth largest company in the world by the late 1920s.
While the cost of smelting the complex copper-bearing ore was high, after the American Civil War, investors like William Andrews Clark and Andrew Jackson Davis began to develop Butte's mines and erect mills to extract the silver and gold. The riches in the hills made Davis Montana’s first millionaire.
By 1876, Butte had become a prosperous silver camp with over 1,000 inhabitants. Marcus Daly arrived that year representing the Walker brothers, entrepreneurs from Salt Lake City. His mission was to inspect the Alice Mine for possible purchase by the brothers. Daly purchased the mine and successfully managed it for the Walkers. The town of Walkerville, which still overlooks the city of Butte, sprang up around the mine and other mines in the area.