Democracy: An American Novel is a political novel written by Henry Brooks Adams and published anonymously in 1880. Only after the writer's death in 1918 did his publisher reveal Adams's authorship although, upon publication, the novel had immediately become popular. Contemporaneous conjecture placed the book under the joint authorship of Clarence King, John Hay and Henry Adams and their spouses who lived side by side on H street in Washington, D.C., and were collectively sometimes called "the Five of Hearts."

Henry Brooks Adams was an American historian and a member of the Adams political family, descended from two U.S. presidents. As a young Harvard graduate, he served as secretary to his father, Charles Francis Adams, Abraham Lincoln's ambassador to the United Kingdom. The posting influenced the younger man through the experience of wartime diplomacy, and absorption in English culture, especially the works of John Stuart Mill. After the American Civil War, he became a political journalist who entertained America's foremost intellectuals at his homes in Washington and Boston.