Ji, Han Jae was born in Andong, South Korea in 1936. At the age of 13 he began his physical training with Choi, Yong-Sul learning Japanese Yawara for about five years. Ji is considered to be Choi’s top student. 

Dojunim’s father wanted him to learn a special style of Martial arts so he began learning Korean Taoist style known as Tek Ki (Taek Kyun). He learned from Taoist Lee who was a practitioner of Sam Rang Do. Sam Rang Do includes Tek Ki and was a traditional Korean Martial arts style during an era before Korea was in existance, when Mongolians ruled the land. Dojunim learned meditation, then weapons and kicking techniques. Eventually he learned to cross Tek Ki with Yawara and made Hapkido. Dojunim learned the spirit side from Taoist Lee’s teacher known as Grandma. Taoist Lee left one day and Dojunim didnt know where he went. Before Taoist Lee left he asked Grandma to teach Dojunim the spirit side. She said yes and called upon Dojunim at Taoist Lee’s request.

In Andong, at the age of twenty-three, Dojunim opened his first dojang (school) and was the first to use the term “Hapkido“. He didnt come up with Yu Kwon Sool but with Hapkido. It was developed along with the Sam Rang Do philosophy: spirit, mind and body; three in one, one body encompassing three facets. All three together make a special you. Ten months later, Dojunim moved his school to Seoul where approximately seventy-five percent of the population lived. In about 1958, Han Bong-Soo of Billy Jack movies began training under Dojunim, and continued to do so until the late 1960’s when Master Han moved to the United States. Master Han and Master Myung Kwang-Shik who is president of the World Hapkido Federation began training under Dojunim around the same time and they were both promoted to 9th Dan respectively, by Dojunim Ji. 

In 1962 Dojunim began his job as bodyguard to the Korean President Park, Chung-Hee which had him working in the Korean Presidential quarters, the Blue House for eighteen years. Dojunim became politically well connected in his job and was in a position of influence. While in Korea, Dojunim was also chief Martial Arts trainer for the three hundred secret service bodyguards protecting President Park, the Korean police and military academies, and the Korean special forces. 

In 1969, the United States Pentagon had an information exchange program with the Korean government, and Dojunim visited the U.S. and trained some of President Nixon’s secret service bodyguards, F.B.I. agents and office of Special Investigations personnel. During this exchange program, Master Jhoon Rhee introduced Dojunim to Bruce Lee, who was impressed with the knowledge and abilities Dojunim demonstrated and asked him to teach him.

In the early 1970’s, Mr. Wong from Golden Harvest Film Company hired Dojunim as fight choreagrapher, technical advisor, and trainer to martial arts movie stars, as well as act in several movies. Bruce Lee had Dojunim wear a golden belt to represent the highest level of Martial Artist for their fight scene in Lee’s final movie “Game of Death”.

Dojunim came to the United States in 1984 and started teaching Sin Moo Hapkido. He taught in several locations including San Francisco, Pacific Grove, Monterey and New Jersey developing many students and instructors. Dojunim continues to teach and expand Sin Moo Hapkido throughout the world.