The Fort William War Veterans were the first representatives of the Thunder Bay region, winning the 1922 Memorial Cup as Canadian National Junior A Champions.

[1] Although there is not abundant information on the subject, the Thunder Bay Junior Hockey League may date back to the War Veterans and existed until 1980.

From 1980 until 2000, the region (Hockey Northwestern Ontario) was represented by a single team at the junior A level: the Thunder Bay Flyers.

[7] In 2006, the Fort William North Stars won the Dudley Hewitt Cup with a 7–6 overtime win over the Northern Ontario Junior Hockey League's Sudbury Jr. Wolves to earn the team and the league its first regional title and its first shot at the national title in the 2006 Royal Bank Cup.

[8] The North Stars were eliminated in the Royal Bank Cup semifinal in Brampton, Ontario, with a 3–2 overtime loss to the British Columbia Hockey League's Burnaby Express led by eventual NHL player Kyle Turris.

The presence of the SIJHL in Northwestern Ontario marks the first time since the 1970s that the region has effectively supported a junior hockey league.

The Fort Frances Jr. Sabres claimed that they would be back for 2009–10, but their owners sold the rights to their players to teams across Canada.

The Thunder Bay Wolverines elected to apply for promotion to the SIJHL for 2009–10 fresh off of their silver medal performance at the Keystone Cup Canadian Jr. B Championships.

The decision was appealed and on July 12, 2011, expansion was allowed by USA Hockey as well as the continuation of the Duluth and Spooner franchises.

Wisconsin won their second straight league title, coming from behind in the final to beat the Fort Frances Lakers in seven games.

Then, after clinching their third regular season and playoff crowns, the Wilderness won the league's second ever Dudley Hewitt Cup as Central Canadian champions.

The Alberta Junior Hockey League's Brooks Bandits scored in overtime to win the game 5–4 eliminating the Wilderness.

With the Wilderness and Clydesdales gone, the Minnesota Iron Rangers were the remaining American team with membership in the league.

[19] The league added a second team in Minnesota and their sixth franchise for 2016–17 season with the Thief River Falls Norskies.