Sam McClure was born in a two-room cottage in Ireland. When Sam was eight, his father died. The family had relatives in Indiana, so his mother took her three children to America. It was in Indiana, one Fourth of July, that young Sam heard a congressman give a speech. "He talked about the land of freedom, of unbounded opportunities," Sam wrote. "I had never heard such a speech before. I felt that, as he said, here was something big and free—that a boy might make his mark on those prairies."

At age fourteen, with a dollar in his pocket, Sam left home. He headed for Knox College in Galesburg, Illinois. But he didn't have enough money for college; so he worked, went to college, dropped out to earn more money, went to college, and worked some more. When he graduated, he went to Boston. Soon he was editing a biking magazine called Wheelman; he realized that what he really wanted to do was be an editor. In 1892 he founded McClure's Magazine. Not long after, he received an article from an unknown author about paving the streets of Paris. It was from Ida Tarbell. Sam McClure could spot talent. Tarbell was an outstanding writer. Eventually, Sam encouraged her to write a book about America's most powerful citizen, John D. Rockefeller, and his giant trust, Standard Oil.

Tarbell spent four years writing two books that were shockers. She showed how Rockefeller's Standard Oil Company took unfair advantage of its competitors. She showed how its uncontrolled power had spread into railroads, mining, and banking, and how that power affected the lives of most Americans. "Mr. Rockefeller has systematically played with loaded dice, and it is doubtful if there has ever been a time since 1872 when he has run a race with a competitor and started fair," she wrote. "Business played in this way is fit only for tricksters."