Yup there's even a very fascinating documentary about this called Waiting For John Frum. It traces the history of background from the insane colonial administra

Yup there's even a very fascinating documentary about this called Waiting For John Frum. It traces the history of background from the insane colonial administration to what led to the development of the John Frum cult. Basically the gist as I understood it is that when Christian colonial missionaries arrived on Tanna Island, they banned all the local religious practices and quickly established themselves as the sole administrator and authority on the island (giving out harsh discipline and torture basically to maintain this power). Once WWII comes around, all the missionaries fled, and soon the Americans arrived bringing with them cargo and gear and importantly, employment and autonomy. Locals were used as couriers and carried supplies in support of the Americans, and in return were given "goods" that were to them simply unheard of before. When the Americans left, the colonial missionaries returned, but because so many people gained this autonomy and ability to practice their former religious ideas, this "cargo cult" formed which essentially was formed by anyone who refused to partake in the Christian authoritarianism that was running the island. People joined simply because it allowed them to have freedom and autonomy and the movement basically fused previous religious practices with these rituals that the Americans brought. The "dream" for John Frum (i.e. the Americans) to return really meant a dream for independence and the Christian missionaries to leave.