Chang Moo Kwan is a style of Korean martial arts that was founded by Yoon Byung-in and Lee Nam Suk.
Lee Nam Suk's teacher Byung In Yoon had founded the "YMCA Kwon Bop Bu" (권법무) in 1946.
He deflected and evaded the karate students’ strikes and kicks to the point that they gave up and ran back to tell their teacher about what happened.
Eventually, the united kwans under leadership of Choi Hong Hi founded this unified national Korean art and named it Taekwondo.
In September 1961 the Korean Taekwondo Association (KTA) was formed and Lee Nam Suk was appointed as the organization's Chair of General Director in 1961.
[5] In the early YMCA Kwon Bup Bu and Chang Moo Kwan, the curriculum mainly consisted of karate and chuan-fa (McLain, 2009).
This was one of two Kwans to have been influenced by Chuan-fa(Kwon Bup), which gave the techniques a smooth yet hard appearance when practiced or demonstrated.