The school was first known as KANBUKAN, "KOREAN MARTIAL ARTS PLACE", founded in 1940, in Tokyo, Japan.  The founder of the Kanbukan, was a Korean school teacher, Geka Yung.  He was the first head of the school to become known later as RENBUKAI. The dojo was a small gym where different martial artists went to practice and exchange thoughts. Geka Yug returned to his homeland in 1949 to teach at a Korean University.

Another influential teacher in the development of Renbukai was Hiroyasu Tamae, born in 1906.  He was a student of the famous Shiroma Gusukuma, who himself was a direct student of Yasune Itosu, the famous Okinawan master of SHURI-TE. Tamae also trained in CHINESE KEMPO in Peking, China before World War II. He also trained at the Okinawan's master school, and trained in both NAHA-TE and the BO. These men all had a strong influence in the roots of the style that evolved into becoming THE ULTIMATE MARTIAL ART: RENBUKAI

In 1945, two young men, NORIO NAKAMURA, a 4th degree in Kendo and a 2nd degree in Judo, and MINORU OKAMOTO a martial artist also became students at the Kanbukan. These two men later became the leaders in the Renbukai movement.  In 1948, MASAYUKI KOIDE, a Shotokan practitioner from Waseda University and a 2nd degree in Kendo joined the Kanbukan school. Koide went on to become the International director of Renbukai.

In 1950, under Norio Nakamura the school became known as the Renbukan, "Training Martial Arts Place. Nakamura went on to become the first director of Renbukan.

It was not until 1964, that the school took the name of Renbukai and became a style of its own. At that time, Renbukai joined KYO-KAI, WADO-RYU, SHITO-RYU/b, GOJU-KAI and RENGO-KAI, in becoming the first six recognized schools as members of the "FEDERATION OF ALL-JAPAN KARATE-DO ORGANIZATIONS. Nakamura continued as the director of Renbukai until 1972, at that time Minoru Okamoto became the director.

In the early sixties, GORDAN KENNEDY introduced what was to become Renbukai to the United States. Kennedy had discovered the Renbukai school while serving with the U.S. armed forces in Japan and had achieved the rank of 1st degree black belt. In August 1964, RON MARCHINI started instruction in the art of Renbukai from Kennedy and senior student F. "BOOTS" CURETON II.  From this beginning, Marchini made his first journey to the Orient in 1966 to train under Norio Nakamura and Masayuki Koide. This was the first of many trips Marchini made to the Orient to study the martial arts.  JAMES GRADY started training with Ron Marchini in 1965. Marchini went on to become the highest ranking martial artist in Renbukai in the U.S. and James Grady the second highest. The two became the most famous of Renbukai practitioners in the world.

Though Renbukai is not widely known in the western world due to the lack of English spoken in the Renbukai organization, it has over 300,000 practitioners in Japan. Renbukai is the only style in Japan to practice fighting full-contact with protective gear. This is done during all training classes and in tournaments to invoke realism. The first full-contact tournament was held in 1954 in Tokyo, Japan.