Ji Han Jae, Dojunim (Founder) was born in 1936 in Andong, Korea. He began his martial arts training in Yawara with Choi, Yung Sul at the age of 13. The techniques he learned at this time were primarily joint locks, throws, low kicks, and sword techniques. He trained full time with Choi until 1956. When Ji was eighteen, he began to train with a man he used to refer to as Taoist Lee Dosa. Ji used the term “Taoist” when he first arrived in the US when talking about Lee Dosa because it was the closest word he could find to describe him. Still it would be more accurate to understand Lee not as a Taoist but a wise man, with incredible martial skills, who followed ascetic practices. Lee was Ji’s Samrangdo Taekky instructor. Lee trained Ji, primarily in mediation, the use of the Jang-Bong (6' staff), the Dan-Bong (short stick), and in Korean Taek-Kyun kicking. With many kicking techniques and high jumping techniques, Ji had a perfect complement to the grounded techniques of Yawara taught by Grandmaster Choi. Lee also began Ji on his mental and spiritual training. He trained him in numerous meditation and breathing exercises. He trained with Lee for almost five years after which he continued his training with Lee’s instructor, “Grandma (Halmeoni).” Ji would spend hours with Grandma at a temple that was a healing complex for terminally ill individuals. He spent about 3 years with her and considers Grandma to be his spiritual teacher. He continued training with her until he left Korea.

Ji, Han Jae, opened his first dojang in Andong,at the age of 23. He called his new school the Moo Kwan and taught Yu Kwan Sool. After 9 month he relocated the Dojang to Seoul in September of 1957. Hwang, Duk Kyu, was his first student at this dojang, called Sung Moo Kwan. During April of 1960 Ji began to piece together the Yoo Sool (Yoo kwan Sool) teachings of Grandmaster Choi, with the methods of meditation, the Taek -Kyun kicking techniques, and the weapons techniques learned from Lee, along with the spiritual training he received from Grandma. The product was “Hapkido.” He had originally thought of calling it "Hapki-Yoo -Kwan-Sool," but decided against that, feeling it was too long. Instead he opted for using the word 'Do' meaning a path to follow, or a way of life, rather than simply 'techniques' as 'sool' implies. When General Park, Chung Hee (1917-1979) became the Korean President in May of 1961, Ji was teaching at the Korean military academy. After a demonstration and with assistance from Major Lee, Dong Nam, Ji was given permission to instruct the military Supreme Council in Hapkido techniques. Ji then received a government position teaching Hapkido to the President Security forces called the Blue House (a position he would hold until Park's death in 1979). In 1963, Ji, Han jae, Choi, Yong sool, and Kwon, Jang instituted the Korea Kido Association. In 1965, Ji, Han Jae left the Korea Kido Association and established the Korea Hapkido Association.

Three dominant Hapkido organizations began to immerge during the next five years. They were the Korea Hapkido Association (founded in 1965 by Han-Jae Ji), the Korea Hapkido Association (founded in 1969 by Jae-Nam Myung), and the Korean Hapkido Association (founded in 1971 by Kim, Moo Woong). Eventually, in 1973, the leaders of these organizations met and agreed to unify their associations. The new association was named Dae Han Min Kuk Hapkido Hyub Hwe (Republic of Korea Hapkido Association). From 1967 to 1969, Ji traveled to Vietnam with some of his students to teach Hapkido to the US and Vietnamese and Korean soldiers fighting there. Ji first came to the United States as part of an exchange with President Richard Nixon’s security forces. He taught Hapkido to the US Secret Service, Special Forces, OSI, FBI, and CIA. While he was visiting and staying at Andrews Air Force Base, his good friend, Taekwondo Grandmaster Jhoon Rhee, introduced Ji to Bruce Lee. Lee was impressed with Ji’s techniques and asked him to teach him. Ji taught Lee and also traveled to Hong Kong over the next few years to help choreograph martial arts movies and also star in a few of them. At this time, Ji taught movie stars such as Jin Pal Kim, Angela Mao, Samo Hong among many others. He appeared in three movies, Hapkido (Lady Kung Fu), Fist of the Unicorn Palm, and Bruce Lee’s Game of Death. Extra footage of Game of Death was recently released as a movie called A Warrior’s Journey, which features 18 minutes of fight scenes featuring Ji.

Ji traveled to Germany to teach for three months in 1984. It was at this time that Grandmaster Ji, Han Jae began teaching Sin Moo Hapkido (pronounced “shin moo”) and formed the Korea Sin Moo Hapkido Association. “Sin” means higher mind (the old character could be translated to mean “godlike,” but the meaning Ji refers to is simply “higher mind” or “mental.”) “Moo” means martial art. Simply put, Sin Moo means, “Higher mind martial art.” Much of the techniques are the same as what he taught while in Korea, but the emphasis has changed. The Sin Moo focuses more on the mental and spiritual aspects of Hapkido as well as controlling Ki or Qi and being able to use it effectively. Dojunim has also expanded the weapon repertoire to include the cane, handkerchief or rope, knife and projectiles throwing techniques. Today there are still several dominant Hapkido organizations in Korea. These include, the Korea Kido Association, the Korea Hapkido Association, and the International Hapkido Federation. The Korea Hapkido Association is still the most prominent Hapkido organization in Korea. The graduates of the Original Sung Moo Kwan make up the majority of its senior instructors. Dojunim Ji Han Jae is Master Marquez' direct master instructor, mentor guide and teacher.