Ed Parker was the founder of American Kenpo and opened the first school of this style in 1954. He was a native of Honolulu, Hawaii, and originally learned Karate there, but moved to Utah and finally to California after graduating from B.Y.U. (in Utah).
He was a Karate technical advisor for television and film in the United States (even appearing on the movie Trail of the Pink Panther), taught Karate to many famous people, including Elvis Presley and Blake Edwards, the creater of Pink Panther, and was even known as "the High Priest and Prophet of the Hollywood sect [of Karate]," (by Time Magazine).
He invented American Kenpo after noting the need for a more practical form of self-defense, one that was not so much rooted in the mysticism of previous styles, but one rooted in the needs of the vulnerable men and women of the present. American Kenpo was especially remarkable for the fact that several moves could be done simultaneously, as well as a more Chinese-based circular movement of the hands and feet (making the style smoother, more akin to Kung Fu than Tae Kwon Do or Shotokan).
Ed Parker also wrote several books, such as six in the series Infinite Insights into Kenpo (as well as many others), and is considered the man that introduced Karate to the United States.
Ed Parker died on December 15, 1990 (thanks Sandor, for correcting me).
Sources: Infinite Insights into Kenpo: 1. Mental Stimulation (book) by Ed Parker