Upton Beall Sinclair Jr. (September 20, 1878 - November 25, 1968), was an American author and one-time candidate for governor of California who wrote close to one hundred books in many genres. He achieved popularity in the first half of the twentieth century, acquiring particular fame for his classic muckraking novel, The Jungle (1906). It exposed conditions in the U.S. meat packing industry, causing a public uproar that contributed in part to the passage a few months later of the 1906 Pure Food and Drug Act and the Meat Inspection Act. Time magazine called him "a man with every gift except humor and silence."
He won the Pulitzer Prize for Fiction.