With the exception of Heihei (who is, mind you, a chicken with no dialogue) and the elderly villager who wants to eat Heihei (both played by Alan Tudyk), all of the film's speaking roles are performed by actors with Hawaiian, Samoan, or Māori ancestry, and the only singing done by non-Polynesian performers are Christopher Jackson, who sings Chief Tui's parts, and Lin-Manuel Miranda, who sings the English portions of "We Know The Way".
Dwayne Johnson (Maui) is half Samoan; Oscar Kightley (who plays a fisherman) is Samoan, and former Pittsburgh Steelers player Troy Polamalu (the villager with the leaking roof) is also Samoan.
Auli'i Cravalho (Moana) and Nicole Scherzinger (Sina) are part Native Hawaiian.
Rachel House (Grandma Tala), Temuera Morrison (Tui), and Jemaine Clement (Tamatoa) have Maori ancestry.
The te reo Māori dub adds Māori voice actors Jaedyn Randell (Moana), Piripi Taylor (Maui), and Amanda Ashton (Sina) to the original Māori cast members.
Awesome, Dear Boy: Part of why Dwayne Johnson agreed to the role was the thrill of seeing his Polynesian ancestry so beautifully depicted in a major motion picture, and he admitted to crying Tears of Joy over it many, many times during production.
Cash Cow Franchise: More Moana merchandise is sold than that of Frozen. It helps that unlike Frozen, it appeals to both young boysnote Not just older male viewers aware of the Girl-Show Ghetto phenomenon, who were a Periphery Demographic for Frozen. and young girls, since it has one female lead and one male lead.
Celebrity Voice Actor: In the Norwegian dub, Tamatoa is voiced by famous and seasoned singer Bjørn Eidsvåg, making it his first time ever voicing in an animated film.
Moana marks Christopher Jackson's third time working with Lin-Manuel Miranda, since both previously appeared in the original Broadway productions of Miranda's In the Heights and Hamilton. Phillipa Soo who was also in the original Broadway Cast of Hamilton is credited as an "additional voice".
The original idea was for the film to branch away from the Disney Princess template and focus entirely on Maui, with the story being a loose conglomeration of a few of the legends about him. Then the crew actually traveled to Polynesia and became so fascinated with the culture that Moana was created as the new focus character.
There are a few songs that never made it into the final product. For example, Lin-Manuel Miranda's Unstoppable. (WARNING! The song includes spoilers for the movie.) Although some parts of those songs did end up being used; the instrumentals in the beginning of "You're Welcome" are very similar to "Unstoppable", and part of the lyrics of "More" ended up in "How Far I'll Go" (the "Every turn I take..." bit).
Heihei was originally conceived as a much more serious, no-nonsense character that was determined to keep Moana out of trouble and remaining on the island, sort of like a SebastianExpy. However, the chicken became unlikable, so they went in a totally different direction. Pua also had a larger role in earlier drafts, but it was decided that having an adorable, intelligent animal along for the ride would give Moana too much comfort on her journey.
Some sources suggest that the Kakamora battle scene is what ultimately saved Heihei from being dumped entirely. After someone suggested that Heihei could be the story's comic relief, artist Sunmee Joh boarded a funnier version of the Kakamora scene where, instead of just fighting over the Heart of Te Fiti, Moana and the Kakamora were carrying a chicken around the entire time. John Lasseter's reaction to this change apparently gets referenced at the end of the film with Maui's line of "The chicken lives!"
Tamatoa was initially conceived of as a headless giant inspired by such a being in folklore.
Lalotai was originally planned to be more of a traditional underworld (taking the form of a glowing underwater village amongst the coral) where Moana would meet the spirits of her grandmother and ancestors. The goddess Hina would have also been part of this sequence, though depicted as Maui's overbearing grandmother.
In Taika Waititi's first draft of the script, Moana had nine older brothers who were the ones who taught her how to sail (making her the youngest child and only girl) and who she had to go and rescue.
In early drafts, Moana was meant to be 14, but was aged up slightly to 16 for the final product. Coincidentally, Auli'i Cravalho was 14 when she was cast and during recording, and 16 when the film was released. Had she remained 14, Moana would have been the youngest "princess" in the Disney Animated Canon since Snow White (who was also 14).
One scene originally had Moana taking out her anger on some coconuts by batting them out into the sea with a stick like baseballs. This was changed to her throwing sticks when the film's oceanic consultants pointed out that wasting her island's most valuable resource during a temper tantrum, in the middle of a food crisis, would make her less sympathetic.
The directors originally wanted to make a film based on Terry Pratchet's Mort, but a litany of problems meant that they had to abandon the idea and focus on a diffrent film, the end result being Moana.