The four–team Class B level league evolved from the 1918 Pacific Coast International League, with franchises based in Washington and British Columbia.
J. M. Osmond served as president of the 1919 Northwest International League.
The Seattle Giants, Tacoma Tigers, Vancouver Beavers and Victoria Tyrees were the league members.
[2] On June 5, 1919, the Tacoma Tigers franchise folded, leaving the league with three remaining teams.
[3] The Pacific Coast International league reformed for the 1920 season.