The most famous name in chewing gum is William Wrigley Jr., who created iconic brands including Doublemint and Juicy Fruit in the factory he started in Chicago in 1898. Wrigley understood the power of marketing and once mailed free gum to over 1.5 million people listed in the U.S. phone book. His fame and fortune speak as much of gum as they do of advertising in general, and Wrigley spawned innovations like those of Topps, which began wrapping gum in comics just after World War II, and added baseball cards to gum packs in 1952.