Ida Tarbell essentially invented modern investigative journalism and used it to dismantle the empire of the wealthiest man in modern history, John D. Rockefeller. She did it with nothing but publicly available documents, microscopic attention to detail, and sheer willpower, a methodology that simply did not exist before her.

Raised in the violent Pennsylvania oil rush and trained in biology under a microscope, she treated corporate corruption like a specimen to be isolated and exposed. Her 19-part series on Standard Oil, built from courthouse records and a smoking-gun stash of scraps, contributed to landmark antitrust action and the Supreme Court ordering the monopoly's dissolution.

• How the South Improvement Company scheme crushed her father's livelihood
• Her biology training and how it shaped her fact-driven research styl ...