The Mid-Western "B" was known as the Waterloo-Wellington Junior "B" Hockey League until 1977 when it donned its current name.
The league was founded in 1973, taking aboard Kitchener Ranger Bs, Waterloo Siskins from the Western Jr. B league, and expansion teams the Caledonia Corvairs and Brantford Diamond Kings.
A year later the Stratford Warriors joined the Waterloo-Wellington league, along with the Preston Raiders, Hespeler Shamrocks and Elmira Sugar Kings.
As there is little information about the league pre-1977, it is easy to say that the Mid-Western "B" was easily dominated by the Stratford Cullitons and the Waterloo Siskins for the first fourteen years of its current existence.
For information on the 2007-08 season, please see: Greater Ontario Junior Hockey League.