Description of Hapki yusul
The meeting of cultures no matter how far or near they are from each other before they meet more often than not causes influence to one or the other, if not both. This is what we could say happened when the Chinese culture met Japanese culture in the ancient times and eventually when the Japanese culture met Korean culture during the Japanese occupation of Korea. Being a great part of these countries' history and culture, martial arts was inevitably influenced as well. Hapki Yusul is one of the martial arts born from a Japanese martial art, which in this case is Daito-ryu Aiki-jujitsu.
For a bit of a background Daito Ryu Aiki-jujitsu, it is a combination of principles and techniques of Jujitsu and Aiki. Jujitsu is basically a martial art that deals with techniques and methods that are useful when facing an opponent that is armed and armored by striking using the proper technique at the proper place at the proper time. Aiki, on the other hand, is based on flexibility and the ability of the practitioner to "blend" with multiple strategies. It could be said that the principles of Aiki create the opportunity that the principles of Jujitsu needs.
Going back to Hapkiyusul, its foundation started with the return of Choi Yong Sul in 1946 from Japan to Korea. He started to teach Daito Ryu Aikijujitsu until his students were able to combine other techniques, eventually forming other martial arts including but not limited to Hapkido, Hwarang Do, Hanmudo, Hanpul and the like. It was in 1987, a year after Choi Yong Sul died, that one of the famous practitioners named Kim Yun Sang began to use the term "Hapkiyusul". This was in order to create a distinction between what Choi taught to what Kim was teaching. Kim taught what Choi taught him and everything was retained in its original form, telling students they were Daito Ryu Aikijujitsu. At the same time, there was a great focus or emphasis on the use of Hapki (Aiki).