The Detroit Lions are a NFL team based in Detroit, Michigan. Originally based in Portsmouth, Ohio and called the Portsmouth Spartans, the team began play in 1929 as an independent professional team, one of many such teams in the Ohio and Scioto River valleys. For the 1930 season, the Spartans formally joined the NFL as the other area independents folded because of the Great Depression. Despite success within the NFL, they could not survive in Portsmouth, then the NFL's smallest city. The team was purchased and moved to Detroit for the 1934 season.