Hapkido History of Hapkido Hapkido Is distinguished by three essential principles: non-resistance when opposing force, circular motion when countering attacks, and the water principle when penetrating an opponent's defenses. For example, if the attack is strong, one would recieve it gently or absorb it. If the attack is weak, one would counter it strongly. This complementary manner of reacting establishes a perpetual and liquid rhythm as well as a constant mobility, the hallmarks of Hapkido. Hapkido was founded by Yong Shul Choi, who from 1919 to the beginning of World War II ,had studied Daito ryu Aiki Jujitsu in Japan. Around !939-40,Choi combined his knowledge of Aiki Jujitsu with the native Korean style of Tae Kyon, the latter chiefly a kicking style. Until the 50's Hapkido was known by a variety of names: yu kwon sul, yu-sool,ho shin sool, and bi-sool. In the early 60's under the leadership of Choi the Korean Kido Association was formed.Choi was assisted by his top students Ji Han Jae, In Hyuk Su, and Moo-wung Kimm. Later a number of these students left and formed the Korean Hapkido Association. Today there are reportedly one million students in each of these associations world wide. There are four major Hapkido pioneers in the U.S: Sea Oh Choi, Ji Han Jae, Bong Soo Han, and He-Young Kimm. Hapkido was introduced into the U.S by Sea Oh Choi who had immigrated to the Los Angeles area in 1964. But the system didn't become popular until the motion picture Billy Jack came out featuring Hapkido in realistic fight scenes choreographed by Bong Soo Han.