Lost Generation is traditionally attributed to Gertrude Stein and was then popularized by Ernest Hemingway in the epigraph to his novel The Sun Also Rises, and his memoir A Moveable Feast. It refers to a group of American literary notables who lived in Paris and other parts of Europe from the time period which saw the end of World War I to the beginning of the Great Depression.
The definitive Wikipedia entry for Lost Generation. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Lost_Generation
