大東流合気柔術
Choi Yong-sool (; November 9, 1904 – June 15, 1986), alternative spelling Choi Yong-sul, was the founder of the martial art Hapkido (Hangul: 합기도; hanja: 合氣道). He was born in today's Chungcheongbuk-do, South Korea, and was taken to Japan during the Japanese occupation of Korea when he was eight years old. Choi later stated that he became a student of Takeda Sōkaku, and studied a form of jujutsu known as Daitō-ryū Aiki-jūjutsu (大東流合気柔術) while in Japan. This is disputed by some parties, due to the historically acrimonious relationship between Japan and Korea, and lack of clear documentary evidence (see below).