In 1923 the Karate Master Gichin Funakoshi formally introduced Okinawa karate to Japan. He is believed to be the first person to teach Karate publicly in a dojo (training hall). His style was given the name Shotokan, (from his pen name Shoto) and he attracted numerous students. One of his top students was a young man named Mas Oyama who at the age of 20 had achieved a Black Belt Fourth Dan. After many years of training Oyama felt that Karate was missing certain essential elements of effectiveness and to find the answer he retreated to the mountains in isolation. He dedicated himself to daily meditation and vigorous training for 18 months. With his skills greatly refined he returned to society and held public demonstrations to prove his Karate effectiveness. He could be seen breaking stones, tiles, boards, and even fighting bulls. Due to much interest by the public in his skill he opened his own dojo and named his new style Kyokushinkai (way of ultimate truth). The style incorporates full contact blows to the body and is often referred to as knockdown karate.

In the 1960's Mas Oyama accepted a French student, Roger Lesourd. Roger lived and trained in Japan directly under Mas Oyama and was eventually awarded a 3rd Dan Black Belt along with the title of Branch Chief