Napoleon Hill (October 26, 1883 – November 8, 1970) was an American author in the area of the new thought movement who was one of the earliest producers of the modern genre of personal-success literature. His most famous work, Think and Grow Rich (1937), is one of the best-selling books of all time (at the time of Hill's death in 1970, Think and Grow Rich had sold 20 million copies). Hill's works examined the power of personal beliefs, and the role they play in personal success. Most of his books described principles to achieve 'success'.