[3] After establishing the Tai Iku Dojo in Vancouver in 1924, Sasaki and his students opened several branch schools in British Columbia and also trained RCMP officers until 1942, when Japanese Canadians were expelled from the Pacific coast and either interned or forced to move elsewhere in Canada due to fears that they were a threat to the country after Japan entered the Second World War.

When the war was over, the government required interned Japanese Canadians to either resettle in Canada outside of British Columbia's 'Japanese exclusion zone' (within 100 miles of the Pacific coast) or emigrate to Japan.

[1][9][10][11] In 1923 Sasaki began attending judo-versus-wrestling matches in Vancouver and was extremely disappointed to discover that they were fixed and badly misrepresented judo.

After a year of planning, meetings, and fundraising, Sasaki opened Tai Iku Dojo (体育道場, 'physical education training hall') in 1924.

[1][12][13] It was difficult to secure an appropriate location and the first practices were held in the living room of Kanzo Ui, one of the dojo's sponsors, at 500 Alexander Street in Vancouver.

[1][14][15] Over the next several years new branches of Tai Iku Dojo were established in Steveston (where Tomoaki Doi and Takeshi Yamamoto had already started a club but asked for Sasaki's help), Kitsilano, Fairview, Haney, Mission, Woodfibre, Chemainus, Victoria, Duncan, Whonnock, Hammond, and Vernon.

In 1936 Sasaki promoted all eleven officers in the first cohort to shodan, and in 1937 a six-man team of RCMP judoka placed second in a tournament.

[1][19] Jigoro Kano, the founder of judo who was also an accomplished professional educator and a member of Japan's House of Peers, visited Canada three times.

The second visit was in 1936, during which he asked Sasaki to accompany him to Berlin to make a presentation to the International Olympic Committee (IOC) and participate in a subsequent judo demonstration tour in Germany, France, England, the United States, and Canada.

[20][1][21][22] Japan's attack on Pearl Harbour on 7 December 1941 began the war between the Japanese Empire and the Allies, including Canada.

[24][26] 700 men labelled as 'troublemakers' were sent to Prisoner of War Camp 101 in Angler, Ontario near Neys Provincial Park, 2,150 single men were sent to road labour camps, 3,500 people signed contracts to work on sugar beet farms outside British Columbia to avoid internment, and 3,000 were permitted to settle away from the coast at their own expense.

Few employers there were willing to hire a middle-aged Japanese man, so Sasaki and his wife Sumye started a commercial laundry service for hotels and mining companies.

[32][33][34][35]The Canadian Kodokan Black Belt Association (CKBBA) was chartered in 1956, with Sasaki as its president; its name used 'Kodokan' instead of 'Judo' to differentiate it from Gauthier's organization and give it authority.

In 1958, reportedly after the IJF was unable to contact Gauthier, the CKBBA provided last-minute representation at that year's World Judo Championships.

The COA held a hearing to determine which organization should have jurisdiction, and decided in favour of the CKBBA because it had members across the country and Gauthier's Federation was essentially limited to Quebec.