Ooops, I take that back (sort of). I've just found another article.

"The California roll is a classic example of "American sushi," early fusion cuisine incorporating new ingredients into traditional Asian recipes. Food historians generally credit Ichiro Mana****a, of the Tokyo Kaikan restaurant in Los Angeles, with "inventing" the California roll. The date is fuzzy, though most agree this item was available in the early 1970s. "

http://www.foodtimeline.org/foodasian.html