Kajukenbo was created between 1947 and 1949 at Palama Settlement on Oahu, Hawaii.  It developed out a group calling themselves the "Black Belt Society", which consisted of black belts from various martial arts backgrounds who met to train and learn with each other.  This was the beginning of an evolutionary, adaptive style designed to combine the most useful aspects of the arts.
There are five men credited as co-creators of Kajukenbo, and it is from their respective arts that Kajukenbo draws it's name.

Kenpo emerged as the core around which this new art was built.  Although uncredited by name, other influences included American Boxing (Choo was Hawaiian Welterweight Champion) and Escrima (Emperado also studied Kali and Arnis Escrima).
In the late 1940's, Palama Settlement was a community center in a violent area of Oahu where fist-fights or stabbings were commonplace.  From this environment, the founders of Kajukenbo wanted to develop an art that would be readily useful on the street.  As they trained and fought in and around Palama Settlement, the founders of Kajukenbo quickly gained reputations as formidable street-fighters.  In 1950, Adriano Emperado, along with brother Joe Emperado, began teaching the new art in an open class.  They called the school Kajukenbo Self Defense
From it's beginnings, Kajukenbo was an ecclectic and adaptive art.  As time has passed, Kajukenbo has continued to change and evolve.