Sonic the Hedgehog is known for several elements in his adventures: speed, an evil robot-building doctor and 90s-style attempts at environmental messaging. The latter usually manifests in Sonic freeing small animals from the clutches of Robotnik or Eggman, but this does raise several questions about the games' setting.

As a franchise, Sonic has recently undergone somewhat of a revival, with the release of several popular movie adaptations introducing many new fans to the games that inspired the films. As a result, some may be wondering where exactly the Sonic games take place, namely in relation to where all the non-Robotnik humans are. Sega has been particularly bad about answering this, and the franchise's adaptations haven't helped. Here's what the games have said about their settings, as well as how different versions of Sonic have handled the topic.

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Sonic's Games Are On Earth... Except for When They Aren't

Sonic Adventure on the Dreamcast

The issue of where the Sonic games take place goes all the way back to the original entries in the series on the Sega Genesis. In Japan, these games were simply referred to as taking place on "Sonic's World," though their exact location was mostly on South Island. That wasn't the case early on in the series' English localization, however, with Sonic's planet being explicitly stated as "Mobius." This would be reflected in much of the American media for the franchise, whether it contradicted the game or not.

Things changed when Sonic dashed into the third dimension with Sonic Adventure. This game was clearly set on some version of Earth, as there were humans galore in its relatively modern setting. The same went for its sequel, which featured the human military organization GUN as well as relatives of Eggman's. This marked the point at which the American and Japanese continuities were the same. The last game to have humans at this level, however, was Sonic Unleashed. Since then, the franchise has had a bit of an aesthetic reversal.

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The original Sonic games had much more natural settings, making them feel like a whimsical world full of anthropomorphic animals. Of course, this was made weird by the presence of non-humanoid animals such as the Flickies, but the relatively cartoony nature of the world made this bit of not-so-subtle environmentalism fit in. More recent games such as Sonic Colors and Sonic Forces have gone back to this, featuring natural-looking animal villages with absolutely no humans besides Eggman.

More recent years have brought forth the "two worlds" theory, which says that the Sonic games have two planets: the humans' Earth and Sonic's world. It's easy to traverse between these two worlds, which explains the history of the Robotnik family as well as Shadow the Hedgehog. Many fans disliked this idea and simply preferred for Sonic's world to be an Earth of humans, animals and anthropomorphic animals. However, Sonic the Hedgehog comic book writer Ian Flynn has stated that this theory is no longer canon to the franchise, muddying the waters once again. Sonic Frontiers may or may not feature humans in major roles, cementing the preferred idea that Sonic's adventures are on a version of Earth.

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Adaptations Have Made Sonic's World and Earth Separate

Sonic the Hedgehog Movie

Back in the day, the biggest adaptations of Sonic were the American cartoons, as well the Archie Comics monthly comic book. These used the Mobius idea, though they did so in different ways. The comic book revealed that Mobius was once Earth, with an alien gene bomb killing much of humanity. Most of the survivors were mutated into Overlanders, while the world's animal population became the humanoid Mobians. The 1993 to 1994 Sonic the Hedgehog cartoon intended to use something similar, with Mobius in fact being a future Earth and not an alien planet that Robotnik found himself on.

The anime series Sonic X didn't name Sonic's world, but it firmly established that it was separate from Earth. Chaos Control through the Chaos Emeralds was the means of going back and forth between these worlds, which is never stated officially but is likely the reason that Eggman was in Sonic's world. The live-action Sonic movies would also make this world separate from Earth -- and in a surprise bit of fan service, Sonic's world is in fact called Mobius. Of course, this is unlikely to ever be referenced in the games, and with the "two worlds" theory supposedly out the window, no one really knows where it is that Sonic does all of his running.