The South Michigan League operated for eight years. The league was Class D from 1906 through 1910 and 1912. The circuit was upgraded to Class C for the 1914 and 1915 seasons. The organization was called the South Michigan Association for two seasons; Class C in 1911 and Class D in 1913.
South Michigan League (D 1906-10, 1912)(C 1914-15)
South Michigan Association (C 1911)(D 1913)
Adrian, MI: 1906-15
Bay City, MI: 1907-15
Flint, MI: 1907-15
Jackson, MI: 1906-15
Kalamazoo, MI: 1906-14
Lansing, MI: 1907-13
Lansing/Mt Clemens, MI: 1914
Saginaw, MI: 1906, 1908-15
South Bend, IN: 1914-15
Tecumseh, MI: 1906-08
Toledo, OH: 1914