Throughout the years, a number of teams in the National Football League (NFL) have either moved or merged. In the early years, the NFL was not stable and teams moved frequently to survive, or folded only to be resurrected in a different city with the same players and owners, while the Great Depression era saw the movement of most surviving small-town NFL teams to larger cities to ensure survival, and franchise mergers were also popular during World War II in response to the exodus of players to war service. Few, if any, of these relocations and mergers were accompanied with widespread controversy.