Richard Sun Sung Kim was born on November 19, 1917, in Papaaloa, Hawaii. His parents were from Nagasaki, Japan and were Japanese citizens of Korean heritage. By the time O’Sensei was born they had settled in Hawaii. Hawaii was a U.S. territory at that time so O’Sensei had dual citizenship with the U.S. and Japan. 

In 1922 O’Sensei began studying Judo under Kaneko Sensei. In July of 1927 he watched a Karate demonstration by Yabu Kentsu, an Okinawan Karate master who was in Hawaii teaching. O’Sensei said this was a turning point in his martial arts career. He was quite taken by Yabu Kentsu and the Karate he taught. This isn’t surprising since many in the world of traditional Karate say Yabu Kentsu may have been the most powerful Karate-ka of all time. Yabu Kentsu was a stickler for basics and focused on the Naihanchi katas. After Yabu Kentsu returned to Okinawa O’Sensei continued to study Karate under Ankichi Arakaki (A disciple of Yabu Kentsu). And after Arakaki’s untimely death O’Sensei studied in Honolulu under Sadeo Arakaki, another disciple of Yabu Kentsu. He also studied under Higaonna Kamessuke, a disciple of Choki Motobu.

In 1933, O’Sensei trained with Matsu Mizuho (Mizuho Takeda), a student of Gichin Funakoshi. Along the way he also trained with Tachibana Sensei of Honolulu. 

O’Sensei studied boxing at the Sato Gym in Honolulu. He sparred with Midget Wolgast, world flyweight boxing champion. O’Sensei had a professional boxing record of 42 – 0. 

In the mid-1930’s, after his third year at the University of Hawaii, O'Sensei joined the U.S. Merchant Marines, which allowed him to travel to Japan. There he trained with many masters including Yabu Kentsu. He met Hiroshi Kinjo who was a Karate expert and, as O’Sensei said, “A walking encyclopedia” of Okinawan martial arts. It was probably his exposure to Hiroshi Kinjo that influenced O’Sensei to study the history of Karate. 

In 1937 O’Sensei met Yoshida Kotaru. Yoshida is considered one of the best all-round martial artists that Japan ever produced. Although O’Sensei trained with many great martial artists throughout his life, he always referred to Yoshida Kotaru as his Sensei. 

While in Japan, O’Sensei studied at the prestigious Budo Senmon Gakko ("Martial Arts Professional School"), which was established under the framework of the Dai Nippon Butoku Kai ("All Japan Martial Virtues Association"). There he studied the Budoju Happan, the eighteen traditional martial arts of Japan. These include Kyujutsu (archery), Sojutsu (spear), Kenjutsu (swordsmanship), and more. 

In these years O’Sensei met and studied with Kenichi Sawai. Sawaii was known to have had 105 no-holds-barred fights in China. He won all of these using just his “Secret” eight techniques. Sawaii taught that you only need to master a few effective techniques. He insisted it wasn’t important how many techniques you know, but rather, how well you know the principles that the techniques are based on. Master the principles, they always apply. He would insist that this is what you must do.

On December 8, 1941, O’Sensei was working as a merchant seaman on the SS President Harrison. The ship had been outfitted as a troop transport and was headed to China to evacuate U.S. Marines. A Japanese warship overtook the Harrison, and the ship and crew were taken by the Japanese. Because of his heritage, instead of throwing him in prison, the Japanese occupying forces called O’Sensei a brother-in-arms and placed him under "house arrest", which left him free to roam about in Shanghai. He remained in Shanghai throughout WWII.

In Shanghai, O’Sensei attended St. John’s University and Tung Wen College. He also studied T’ai Chi Chuan under Chen Chin Yuan, Yi Chuan under Wang Xiang Zhay, and P’a Kua (Baqua Zhang) under a mysterious Taoist monk, Chao Hsu Lai. He learned Shorinji Ryu kenpo (Shaolin Gung Fu) from Chao Hsu Lai which is said to provide the framework for Shorinji-Ryu Karate that O’Sensei developed. Also, while in Shanghai he again met up with Yoshida Kotaru.

At the end of WWII, in September of 1945, O'Sensei boarded a hospital ship in China bound for Naha, Okinawa. From there he headed to the U.S. on the USS Sanctuary and arrived in San Francisco, California in October of 1945. Three months later he returned to Japan. There, he lived with and again trained under Yoshida Kotaro, this time for seven years. Mas Oyama (founder of Kyokushinkai Karate) was also a student of Yoshida, and Oyama O'Sensei and Kim O’Sensei became good friends. Yoshida sent O’Sensei and Oyama to train with Aikido master, Morihei Ueshiba, in Wakamatsu Cho. The two were also sent to study with Goju-ryu master, Gogen Yamaguchi. Both O'Sensei and Oyama Sensei received their black belt ranking in Goju-ryu. 

O’Sensei had the opportunity to train with Kobudo masters, including Kanken Toyama and Hiroshi Kinjo. In 1948 he moved to Yokohama, Japan, where he taught a mixture of Shorinji Ryu Karate, Judo and Kobudo throughout the 1950s. Finally, in 1959, O’Sensei Kim returned to the United States. He taught at various dojos and in 1964 he began teaching at the Chinese YMCA in San Francisco’s Chinatown. This became the headquarters for the young ZBBK.

For the next 41 years, O'Sensei taught students from around the world the principles, techniques, and philosophy he'd accumulated and perfected.

O'Sensei died in Sacramento, California on November 8, 2001.