Watch Modern Marvels Season 13 Episode 17 Online

More than a century ago two men controlled nearly all of U.S. copper production, transforming Butte, Montana from a washed-up gold-mining camp into a global powerhouse. William Clark, a ruthless banker known for preying on the misfortune of miners and Marcus Daly, a self-made man with a knack for knowing where to dig, created huge empires and lived like kings, while fighting a ferocious, personal, battle that lasted nearly 25 years.