Not really about the Hawaiians, but...
about the missionary, whaler/invaders who imposed their way of life, foreign values, morals, greed, evil ways onto an innocent, sweet, non-hostile people. The movie really tells of the despoiling of such a people -- like many of meso-American peoples whose ranks were also decimated by the diseases the Europeans brought with them.
Julie Andrews was nothing but a marketing tool for this film.