Grandmaster Clingan was born in Grafton, West Virginia on December 15, 1944. He was the 14th child born to William D. Clingan Sr. and Clara (Kline) Clingan, his younger sister was born in 1947. He attended grade school in Grafton until his mother and family moved to Cresaptown Maryland in 1956. It was a short stay in Cresaptown, the family then moved to Cumberland, Maryland where Grandmaster Clingan attended Penn Avenue Middle School and then in 1958, the same year he began his martial arts adventures, he started classes at Fort Hill High School, where he graduated in 1962. Grandmaster Clingan immediately joined the Air Force and was sent to Osan Air Base, Korea, he continued his training alongside renowned martial artists such as Grandmaster Ki Yun Yi, and many other well-known Korean Grandmasters; many of whom he remains in contact with. His early training began in-depth when he met Grandmaster Yi at Osan Air Base; Grandmaster Yi continues to mentor Grandmaster Clingan to this day. Grandmaster Clingan made two additional trips to Korea and the extensive training he received while stationed at Osan included the privilege to train with Grandmaster Bong Soo Han, the founder of the International Hapkido Association.