Historian James Truslow Adams often receives credit for first popularizing the idea of the American dream. In his 1931 book "The Epic of America," Adams described "that dream of a land in which life should be better and richer and fuller for everyone, with opportunity for each according to ability or achievement" [source: Adams].
But the concept of the American dream, as Adams defined it, actually existed long before him. In 1630, John Winthrop gave his "city upon a hill" sermon to his fellow Puritan colonists as they sailed to Massachusetts in 1630. Although Winthrop never used the word "dream," he eloquently detailed his vision of a society in which everyone would have a chance to prosper, as long as they all worked together and followed Biblical teachings [source: Winthrop]. Gradually, that dream of opportunity evolved in colonists' minds into a God-given right. In the Declaration of Independence in 1776, Thomas Jefferson asserted that everyone in America -- at least, those who weren't enslaved by the colonists -- was entitled to "life, liberty and pursuit of happiness" [source: Jefferson].
As America evolved and grew throughout the 19th century, so did the notion that America was different from other countries: It was a land of unparalleled opportunity, where anything could be achieved if a person dared to dream big enough. Alexis de Tocqueville, a Frenchman who visited the new nation in the 1830s, called this belief "the charm of anticipated success" [source: Cullen]. American transcendentalist philosopher Henry David Thoreau, in his 1854 book "Walden," articulated it this way: "If one advances confidently in the direction of his dreams, and endeavors to live the life he has imagined, he will meet with a success unexpected in common hours" [source: Thoreau].
The words "American dream" gradually began to appear in newspaper articles and books in the mid- to late-1800s, often in reference to hardy pioneers who headed westward to seek fortune, or to European immigrants who arrived in U.S. ports in search of better jobs and homes. By the early 20th century, it was a euphemism for upward economic mobility -- the prototypical American rags-to-riches dream. In Sherwood Anderson's 1916 novel "Windy McPherson's Son," for example, the author described his protagonist as "an American multi-millionaire, a man in the midst of his money-making, one who had realised the American Dream" [source: Anderson].
How did Americans' vision of prosperity further evolve in the 20th century?