During the Mounties' first two seasons, 1956–57, the PCL still was a member of an experimental organized baseball ranking, the Open Classification, as it made a bid for Major League status.

The city had previously hosted numerous clubs at lower levels, including the Horse Doctors (1905; 1907), Beavers (1908–17 and 1922, although the team was alternatively known as the "Champions" and "Bees" in 1912–13 and 1915), Maple Leafs (1937) and Capilanos (1939–42; 1946–54).

[2][3] The first edition of the Mounties was created after the 1955 season when the Oakland Oaks, a PCL member since 1903, relocated because of falling attendance and a dilapidated home stadium.

This pattern continued through 1962: Vancouver fans supported the Mounties during years when they ranked high in the PCL standings, and stayed away when the team was at the bottom.

Four of the Association's six franchises survived, including the Dallas-Ft. Worth Rangers, which joined the 1963 Pacific Coast League—where it displaced the Mounties and inherited their Twins' affiliation and playing roster.