'Cowabunga' was a word introduced by which series character on "The Howdy Doody Show"?

In 1953 the term 'Cowabunga' was first used by Chief Thunderthud on the children's TV show "The Howdy Doody show". With this word Cowabunga, it had its origins in the nonsense word "kawabonga", invented by Edward Kean. He was the writer of "The Howdy Doody Show", which ran in the U.S. from 1947 until 1956. The word Cowabunga was not one stemming from ancient Greek nor Latin nor any romance language. It was just a creation of a TV writer working in the '50s.

Chief Thunderthud, a key character on the show, started every sentence with the nonsense word "kawabonga" or with the syllable "kawa" followed by ordinary English words. Some other native American characters from different tribes, such as Chief Featherman or Princess Summerfall Winterspring, used the word 'kawagoopa' as a greeting or to voice frustration or surprise. With another comic character (Chief Thunderchicken), he used "Kawa Chicken!" when he talked. These words were used by the characters to normally express greetings, joy, frustration, shock, excitement, anticipation, something awesome, solidarity, etc.

Chief Thunderthud really liked to use the word (Cowabunga) because he loved the sound of it. During the 1950s and 1960s surfers in Hawaii adopted 'kawabonga!' as a declaration of enthusiasm. Some of them would change the pronunciation slightly to 'cowabunga!'. 'Kupaianaha' is the Hawaiian word for surprise or wonderful. This word may have influenced surfers who had grown up with "The Howdy Doody Show".