Nintendo's recent Animal Crossing: New Horizons Nintendo Direct nonchalantly revealed a fact with big implications for the series' lore: It appears Animal Crossing games take place on a version of real-life Earth. Since Animal Crossing's world is one populated by humanoid animals and relatively few humans, this Earth may have fallen victim to some kind of apocalyptic catastrophe.
The Animal Crossing Nintendo Direct detailed several new features coming to the series' latest outing, including terraforming, increased house customization, temporary friend codes, a radial outfit menu, and more. But early in the Direct, the narrator described another new feature for the game: hemisphere selection. Animal Crossing games have traditionally run seasonal changes on the Northern Hemisphere calendar, so the ability to toggle the game to Southern Hemisphere seasons is a big win for those living on the southern half of the world. This feature was first revealed by a Nintendo representative in the E3 2019 Treehouse Live presentation, but the Direct's in-universe tone suggests the choice is more than an out-of-game convenience.
Early in the Direct, the narrator asks, "Would you like to live in the Northern Hemisphere or the Southern Hemisphere?" Rather than a choice made to ensure real-world seasons coincide with those in the game world, this phrasing implies the player's deserted island is actually located on one of these Earth hemispheres. Animal Crossing games have referenced Earth in the past, with items like the Earth Rug and Globe. Without definitive proof of the games taking place on Earth, though, it was just as likely that these were really just references, and Animal Crossing's planet was instead located somewhere else. Gulliver, a seagull-like villager who also appeared in the Animal Crossing: New Horizons Direct, spoke of real-world countries in previous games and brought players country-themed furniture, but he's also been known to possess a space-travel capable vessel, so he might have only been visiting Earth from the supposed "Planet Animal Crossing."
The hemisphere selection proves all of these references indeed meant Animal Crossing is set on planet Earth, despite Animal Crossing games' cylindrical play areas. This begs the question: Where did the talking, humanoid animals come from? Some of those in the Animal Crossing community wonder if the animal-like villagers could be aliens who came to Earth from somewhere else (see Gulliver's UFO-like spacecraft) and integrated themselves into society. This would explain the differences between the villagers and other in-game animals, like the sea creatures players can catch through Animal Crossing's fishing mechanics.
But unless these aliens simply overpowered the humans, this theory doesn't quite explain why there are so few human characters in the games. One theory parallels those used to explain the Adventure Time cartoon's world: Long ago, some kind of apocalyptic event left very few human survivors. Over many, many years, humans evolved from the way they look in the real world to their "chibi-fied" appearance in Animal Crossing, and other animal species evolved alongside them to become humanoid and intelligent. This long gap in time between today's society and Animal Crossing's also gives explanation to advanced technologies like, again, Gulliver's spacecraft.
Over the millennia it would probably take for all of these creatures to change so drastically, however, Earth's geography would have inevitably shifted, but the globes shown in the Direct look identical to Earth's current continental layout. Perhaps the real origins of Animal Crossing lie in some combination of these two theories. Maybe aliens came to Earth, wiped out most humans, and somehow accelerated animals' and humans' evolution, creating Animal Crossing's inhabitants without affecting current-day Earth too drastically. Sadly, the most likely scenario is that Nintendo really hasn't thought too hard about it.
Animal Crossing: New Horizons will release for Nintendo Switch on March 20, 2020.