Short answers, pulled from the story.
Harper was founded in New York City in 1817 by brothers James Harper and John Harper, originally operating as J. & J. Harper. The company changed its name to Harper and Brothers in 1833 after the two younger Harper brothers, Joseph Wesley and Fletcher, joined the firm.
Harper is the flagship imprint of HarperCollins. HarperCollins was formed in 1990 when News Corporation combined Harper and Row, its American publishing house, with William Collins, Sons, its British counterpart. The Harper imprint began being used in place of HarperCollins in 2007.
Harper and Brothers was founded by James Harper and John Harper, two brothers trained as printers, who opened their business in New York City in 1817. Their brothers Joseph Wesley and Fletcher joined in the mid-1820s, and the company formally adopted the Harper and Brothers name in 1833.
Harper and Brothers published Harper's New Monthly Magazine starting in 1850, Harper's Weekly starting in June 1857, Harper's Bazar starting on the 2nd of November 1867, and Harper's Young People starting in 1879. Harper's Bazar was sold to William Randolph Hearst in 1913 and is now published by the Hearst Corporation as Bazaar.
News Corporation, controlled by Rupert Murdoch, acquired Harper and Row in 1987. In 1990, News Corporation also purchased William Collins, Sons, and merged the two houses to form HarperCollins.
Harper has published Herman Melville, Mark Twain, Agatha Christie, Arthur Conan Doyle, Aldous Huxley, E. B. White, Harper Lee, Martin Luther King Jr., Maurice Sendak, Shel Silverstein, Laura Ingalls Wilder, Thornton Wilder, and Barbara Kingsolver, among many others.