The origin of the American dream started mostly during the later half of the nineteenth century, many of America’s physical resources were undiscovered, allowing the possibility of coming across a fortune through relatively little, but lucky investment in land or industry. Many early Americans prospectors headed west of the Rocky Mountains to buy acres of cheap land in hopes of finding gold. The American dream was a driving factor not only in the Gold rush, but also in the immigration throughout that century and the following. During the mid-to-late nineteenth century Horatio Alger, Jr. became famous for his novel that idealized the American dream. Lots of immigrants came to America to escape the poor quality of life at home. Beginning of the twentieth century, major industry personalities started humble and then were controlling enormous corporations and fortunes. Most notable would be Andrew Carnegie and John D. Rockefeller, great American capitalists. This acquisition of great wealth appeared to demonstrate that if someone had talent, intelligence, and the will to work extremely hard, people were likely to be a success in life as a result. In the twentieth century, the American dream had its challenges. The Depression caused widespread hardship during the Twenties and Thirties, and was almost a reverse of the dream for those directly affected. Many Americans experienced profound hardship in the changing economic landscape. However their wealth were based on material possessions. By the turn of the 20th century, the American dream had begun to lure numbers of immigrants from Eastern and Southern Europe. Huge numbers of immigrants came to find work in industrial cities such as New York, Chicago, Philadelphia and Detroit. This wave of immigration continued until the outbreak of World War I.