Ida Minerva Tarbell is recalled as the writer who blew the whistle on the first and most powerful trust in America. The History of the Standard Oil Company, her most important work, was published in 1904 and immediately convinced the public that the Standard Oil Company and its imitators in other industries threatened the underpinning of democracy--equal opportunity. The Supreme Court of the United States eventually concurred; in a 1911 decision the Court decreed the breakup of Standard Oil. Tarbell became known as the Joan of Arc of the oil regions, a historian who not only recorded history but also helped powerfully to shape it.

The pioneering drive that characterized Tarbell's career came from English and Scottish ancestors who arrived in the midst of the wilderness of seventeenth-century New England. Many of them continued to press westward in a restless search for a perfect life in a perfect place. In...