The only thing the Herrins and the Burkes had in common was their Irish ancestry. Opposites in most ways, the families nevertheless personified two common threads in the history of the West. As the owner of an iconic Montana stock-raising operation–the famous Oxbow Ranch on the shores of Holter Lake–Holly Herrin ruled with frontier violence and legal action over an empire of cattle and sheep that covered thirty square miles. George Burke was a real estate agent, a sheriff, a game warden, and a civil engineer in a family of professionals–newspaper editors, lawyers, and politicians, including a U.S. senator.

The country-mouse Herrins voted Republican, the city-mouse Burkes Democratic. Both patriarchs, fighting with their fists and their lawyers, were active players in the far-reaching dramas and ludicrous comedies that shaped the politics and economy of modern Montana. In 1949 the clans joined their fortunes together when rancher Keith Herrin, Holly’s grandson, married George Burke’s daughter Molly, a wire service reporter. It was a union that produced five girls and one boy–an heir. Twenty years later, the marriage and the Herrin ranches were failing.

The story of the Burkes and Herrins has never been told before, and the history they made has been largely forgotten. The Last Heir recounts twelve decades of Burke and Herrin triumphs and tragedies: the story of Montana’s Missouri River heartland, a history seen through the eyes and daily lives of those who lived it.

Bill Vaughn is a former contributing editor for Outside Magazine. His is the author of Hawthorn: The Tree That Has Nourished, Healed, and Inspired through the Ages.