The NNL survived controversies over umpiring, scheduling, and what some perceived as league president Rube Foster's disproportionate influence and favoritism toward his own team. It also outlasted Foster's decline into mental illness in 1926, and its eastern rival, the ECL, which folded in early 1928. The NNL finally fell apart in 1931 under the economic stress of the Great Depression.
The Negro American League, founded in 1937 and including several of the same teams that played in the original Negro National League, would eventually carry on as the western circuit of black baseball. A separate Negro National League was organized in 1933, but eventually became concentrated on the east coast. To distinguish between the two unrelated leagues, they are usually referred to as the first Negro National League (or NNL I) and the second Negro National League (or NNL II).