Han-Jae Ji was born in 1936 in Andong, Korea. He began his martial arts training in Yoo Sool with Choi in 1949 at the age of 13. He trained full time with Choi until 1956 when he moved back to his home city of Andong. When Ji was just eighteen, he began to train with a man who he refers to as Taoist Lee. Taoist Lee, trained Han-Jae Ji primarily in various methods of meditation, and in the use of the Jahng Bohng (6' stick), the Dahn Bohng (short stick), and Korean Taek Kyun kicking. During the same period, a lady monk known to Ji only as "Grandma" taught him spiritual power for almost five years.

In Andong, Han-Jae Ji, then a 3rd Degree, opened his first dojang which he called An Moo Kwan and began to teach Yoo Kwon Sool. After approximately nine months in Andong, Ji decided to relocate to Seoul in September of 1957. He stayed in a boarding house in Wang Shim Ri. The son of the owner of the boarding house, Duk-Kyu Hwang, became his first disciple at his new dojang, called Sung Moo Kwan.

Ji was also able to open a additional small dojang at a neck tie factory where he had only a few students. These were mainly from Han Yang University and many faced financial difficulties. Finally, Ji's skills and teaching became even better and he decided to move to a more suitable location. He rented a room form a man named Bong-Ah Ko, a local boxing teacher, and for the first time had access to a regular mat where he could conduct his classes.

In 1958, Ji moved his school to Joong Boo Shi Jang where he continued teaching until April of 1960. It was during this period when Ji began to piece together the Yoo Sool (Yoo Kwon Sool) teachings of Grandmaster Choi, with the methods of meditation, the Taek Kyun kicking techniques, and the weapons techniques learned from Taoist Lee, along with the spiritual training he received from "grandma," to formulate his own style of martial art for which he chose the name Hapkido. He had originally thought of calling it "Hapki Yoo Kwon Sool," but decided against that, feeling it was too long of a name. He thought of other martial arts he had heard of, such as Tae-Kwon-Do, Kong-Soo-Do, Soo-Bak-Do, etc., where the word 'do' was being used instead of 'sool'. He liked this idea because the word 'do' means a path to follow, or a way of life, rather than simply meaning 'technique', as 'sool' implies. The name Hapkido was chosen in 1959, and has been used ever since. The word itself is translated as the "way of coordinated power." Where "Hap" means to unify or coordinate, "Ki" means mental and/or physical energy, and "Do" means a way of life, or the 'path' or 'way' of coordinating your mental and physical energy into one entity.

During a conversation this author had with (Grandmaster) Han-Jae Ji in his personal suite after the first day of a grueling seminar, it was related that after he decided on the name Hapkido to represent his art, he gave this name to his teacher, Yong-Sool Choi to use. Choi taught under the name Hapkido until his death in 1986, even though he did not teach the complete curriculum - leaving out the majority of the kicking techniques, and some of the weapons techniques.

The actual Hapkido curriculum was not finalized until the early 1960's after a fellow student of Grandmaster Choi's, Moo-Woong Kim, moved to Seoul to visit and study with his friend Han-Jae Ji. He stayed for approximately eight months, during which he practiced with Ji, and gave his input and advice regarding which kicking techniques should be adopted (Kim had previous Taek-Kyun training). The only significant difference that evolved from this collaboration was that Ji taught that a low spinning kick be done with only the ball of the supporting foot touching the ground; whereas, Kim teaches that the knee and foot are on the ground while the kick executed.

In May of 1961, the Korean government was overthrown by General Chung-Hee Park (1917-1979), an action which ultimately resulted in his being elected President. In 1962, Ji moved to Kwan Chul Dong, in a space in back of the Hwa Shin Department Store. By this time, Ji had built his Sung Moo Kwan school up and it was financially strong. With assistance from Major Dong-Nam Lee, Ji was given permission to instruct the Military Supreme Council in Hapkido techniques. Ji then received a government job teaching Hapkido to the Presidential Security Forces (a position he would hold until Park's death on October 26th, 1979). During this time, he moved his school to Suh Dae Moon (West Gate Section), which he felt would give him greater exposure to the public.

In the early 1960's, Chung-Hee Park lifted import restrictions banning Japanese goods from Korea, after which, Ji came across a book on Japanese Aikido. Ji saw that the Japanese characters for Hapkido were identical to those for Aikido. Discouraged that a Japanese art had the "same name" as Hapkido, he decided to drop the "Hap" from it's name, calling his art simply, "Kido."

On September 2, 1963, the Korean government finally granted a Charter through the Ministry of Education to the Korea Kido Association. They were granted the right to supervise and regulate the standards of teaching as well as promotion requirements of Black Belts in thirty-one different Korean martial arts. The first chairman of the Korea Kido Association was Yong-Sool Choi. The Association tried to promote martial arts to public school students, police officers, and to military officials.

In 1965 Han-Jae Ji left the Korea Kido Association and established the Korea Hapkido Association. There were several reasons for this. First, the Korea Kido Association appointed Jung-Yoon Kim as Secretary-general. Kim, who was a university graduate, dominated the policies of the Association, and Ji did not like this situation. Second, the students that were trained in Sung Moo Kwan under the name of Hapkido, did not like the new term, "Kido." They continued to call their martial art Hapkido, and continued to teach it the way they learned it. The students did not feel that it mattered that a Japanese art had the same name. The two styles were not directly related, and they felt if Hapkido was practiced hard, that this would be better than simply changing the name. They also felt that changing the name could possibly imply defeat without a fight. And lastly, Han-Jae Ji was appointed Chief Hapkido Instructor for the President's Security Forces and had become a powerful person. This power translated into the ability to successfully operate his own organization without help from others who were being less than ethical in their lives as martial artists.

Three dominant Hapkido organizations began to immerge during the next few years. These included, the Korea Hapkido Association (founded in 1965 by Han-Jae Ji), the Korea Hapki Association (founded in 1969 by Jae-Nam Myung), and the Korean Hapkido Association (founded in 1971 by Moo-Woong Kim). Eventually, in 1973, the leaders of these organizations met and agreed to unify their associations as one. The new association was named Dae Han Min Kuk Hapkido Hyub Hwe (Republic of Korea Hapkido Association).

In 1984, Grandmaster Han-Jae Ji moved to the United States and founded Sin Moo Hapkido. That same year, Grandmaster Moo-Woong Kim resigned from the Republic of Korea Hapkido Association, and founded the International Hapki Federation. Grandmaster Se-Lim Oh became the president of the Republic of Korea Hapkido Federation, and late in 1984, he renamed it the Korea Hapkido Association (the name Ji had used in the '60's).

Today there are still three dominant Hapkido organizations in Korea. These include, the Korea Kido Federation (In-Sun Seo, Pres.), the Korea Hapkido Association (Se-Lim Oh, Pres.), and the International Hapki Federation (Moo-Woong Kim, Pres.) The Korea Hapkido Association is still the leader in Korea, and the graduates of the Sung Moo Kwan make up the majority of it's instructors.