His father, Kichibe Uyenishi, had been a famous athlete, noted for his unusual physical strength and skill at kenjutsu, horsemanship, swimming and sumo wrestling.

As he was contemplating a military career, his father encouraged him to begin training in jujitsu and he enrolled in a local dojo; in an interview, Uyenishi noted that it had been the school of Yataro Handa in Osaka,[2] where Mataemon Tanabe taught.

Soon after his arrival in London, Uyenishi joined fellow expatriate Japanese wrestler Yukio Tani on the teaching faculty of Barton-Wright's Bartitsu Club in Shaftesbury Avenue.

During the period of 1907–8, Uyenishi embarked on a highly successful professional tour of Spain, Portugal and other European countries, teaching jiujitsu classes and performing exhibitions and challenge matches with local wrestlers.

[4] Notable individuals who were directly influenced by Sadakazu Uyenishi's teaching included William Garrud whose book The Complete Jujitsuan (published in 1914) became a standard reference work on the subject; Edith Garrud, who went on to establish jujitsu classes for members of the militant Suffragette movement; and Emily Watts, whose 1906 book The Fine Art of Jujitsu was the first English work to record Kodokan judo kata.