Professor "Thunderbolt" Chow

William Kwai Sun Chow July 3, 1914–September 21, 1987

(AKA William Ah Sun Chow Hoon) was instrumental in the development of the martial arts in the United States, specifically the family of styles referred to as kenpo/kempo.

Born in Honolulu, Hawaii he was the third of sixteen children and first son born to Sun Chow Hoon (AKA Ah Hoon Chow) and Rose Kalamalio Naehu. Chow's father came to Hawaii at the age of 19 and worked in a Laundromat as a laborer. His mother was of Hawaiian descent. One of his brothers, John Chow-Hoon, would also become a well–known martial artist. Chow left school at age eleven from the sixth grade.

Professor Chow's first training came from his father teaching him Chuan Fa (Northern Shaolin Kung Fu). Chow studied several types of martial arts as a young man, including boxing, wrestling, jujitsu, and karate. Though he stood no more than 5’2” tall, he was well known for his powerful breaking techniques and powerful, rapid-fire, devastating strikes. Chow eventually studied “Kenpo Jiujutsu” or “Kosho Ryu Kenpo” under James Mitose. As he progressed, he often tested them against US military personnel in street fights or the hoodlums that ran the streets. In spite of this, Chow did not run afoul with the law.

William Chow became one of five people awarded black belts under Mitose. Chow's black belt certificate was signed by Thomas Young, Mitose’s senior student and instructor.

Instruction style

Chow had a reputation for being a tough instructor, although this quote from Sam Kuoha seems to indicate that the intent was to train, not to harm:

“I knew that every training session would be a tough one as I always walked away injured of some sort. He demanded a strong conditioning session and when you do techniques, you had to mean business. He was always a great technician and when he struck…he struck with intense accuracy. He never meant to hurt anyone…but it appears that when he was doing techniques he was heavily involved in what he was doing and you could see that he was “in the moment of attack.” And with that attack he responded equally. Despite his aggressive and tough training, I always learned so much from what he was trying to portray, so in essence I learned to receive as well as give.


Creation of Kenpo Karate

In 1944 Chow began teaching what he called “Kenpo Karate” at the Nuuanu YMCA in Honolulu. As Mitose had never combined his kosho-ryu style with karate, this was a departure for Chow. His many students included Edmund Parker, Joseph D. and Adriano D. Emperado, Ron Alo, Paul Yamaguchi,Abe Kamahoahoa, Bobby Lowe, Ralph Castro, Sam KUOHA, Bill Chun Sr., John Leone, William G. (Billy) Marciarelli (Kachi/Kenpo), and Paul Pung. He did not create or perform many kata but focused more on individual techniques.

Spread of Kenpo Karate

William Chow’s legacy grew as kenpo spread to the United States mainland with Ed Parker (American Kenpo).

Sam Kuoha was one of the first to bring the Kara-Ho System to the Mainland US as it was taught to him without changes. A former law enforcement officer, he had many opportunities to see if the system really worked. He started his first school in Lakeside, Ca, in 1971 with his first student being Ben Kahananui, now a ranking instructor in the Kara-Ho System. Kuoha later took over Chow’s System after his death in 1987.

Warrior ethos

In spite of his heavy influence on the martial arts in the United States and his many notable students, Chow never had a dojo of his own, often teaching in the park and is thought to have lived in near poverty much of the time. Chow referred to his as a “War Art” and focused largely on techniques that he felt worked in the streets.



Sometime in the early 1960’s, Chow renamed his system “Chinese Kara-Ho Kempo”. Chow died of a cardio ventricular accident due to hypertension. His death certificate was signed by his personal physician, good friend and advisor, Dr. Ronald Perry, M.D. Dr. Perry later in 1988 signed and notarized a certificate for Sam Kuoha promoted him to 10th degree black belt according to Chow’s wishes.

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