The existence of two distinct major league baseball teams in Chicago is the result of nineteenth-century league expansion, territorial rights, and baseball governance history. The Chicago Cubs were already firmly established as the city's lone National League powerhouse when baseball's landscape shifted at the turn of the twentieth century with the creation of the rival American League. To establish a strong foothold in the lucrative Midwest market, the new American League placed a franchise on the South Side of the city, successfully challenging the National League's monopoly. This dynamic created a permanent two-team metropolitan market, dividing the city along geographic and cultural lines into proud North Siders and South Siders.