According to the New York Times, in her new book, Dark Money, New Yorker staff writer Jane Mayer reports that the father of the billionaire Koch brothers, whose fortune they inherited, helped to construct a major Nazi oil refinery personally approved by Adolf Hitler.

The book explores the history of several wealthy families at the heart of American conservatism. From the Times:

The book is largely focused on the Koch family, stretching back to its involvement in the far-right John Birch Society and the political and business activities of their father, Fred C. Koch, who found some of his earliest business success overseas in the years leading up to World War II. One venture was a partnership with the American Nazi sympathizer William Rhodes Davis, who, according to Ms. Mayer, hired Mr. Koch to help build the third-largest oil refinery in the Third Reich, a critical industrial cog in Hitler’s war machine.

“If the content of the book is reflective of Ms. Mayer’s previous reporting of the Koch family, Koch Industries or Charles’s and David’s political involvement, then we expect to have deep disagreements and strong objections to her interpretation of the facts and their sourcing,” Ken Spain, a spokesman for Koch Industries, said.

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