The Milwaukee Road was a direct competitor over many of its routes with the Chicago & North Western. Both offered a dozen trains a day between Chicago and Milwaukee and several more trains a day to various cities in Iowa, Minnesota, South Dakota, and Wisconsin. Until 1955, the North Western had the advantage of being the favored partner with the Union Pacific for its trains to the West Coast. The Milwaukee had its own like to the West Coast which, unfortunately, was tertiary in importance after the GN and NP.
For what it’s worth, the 1940 Milwaukee timetable was 20 pages shorter than the North Western’s 1939 timetable. Where the North Western had more than 120 tables (not counting connecting roads), the Milwaukee had 106.