The Pokemon series generally plays it loose when it comes to the franchise’s timeline. While Pokemon Legends: Arceus is clearly set earlier than other games in the core franchise, when it exactly takes place has become a mystery that many fans are trying to solve. Given the habit of characters in the series going through noticeable lengths of time without aging, trying to pinpoint exactly when the Pokemon Legends: Arceus' events take place could be a near-impossible task. Luckily, there have been some guidelines set for when certain events in the Pokemon series happen, and these can be used to deduce Pokemon Legends: Arceus position.
Some of the clearest hints about Pokemon Legends: Arceus comes directly from media released about the game. The fact that the region players are familiar with from the original Pokemon Diamond and Pearl games is called Hisui, but there are still the references to Sinnoh, suggests an age far enough back that the entire region’s name is changed based on this figure. On the other hand, given the ability to craft Poke Balls and catch Pokemon, fans can deduce that it's late enough in Pokemon’s history that modern methods for taking in Pokemon as partners are available.
The Pokemon Series Timeline
The information that’s been openly given about the time that Pokemon Legends: Arceus is set in is still lacking, though. The best resources that fans have for understanding when any of the games take place come from outside of Pokemon teasers and trailers, relying instead on information scattered across the internet. One of the most notable is a series of deleted tweets that may need to be taken with a grain of salt, but set the foundation for understanding the Pokemon franchise’s timeline as a whole. These Tweets keep everything tidy leading up to Gen 8 where Pokemon introduced Mega Evolutions and Fairy Pokemon in Pokemon X & Y.
Writer Toshinobu Matsumiya posted a set of since-deleted Tweets as far back as 2014 outlining a general timeline. Here, Gen 1 and 3 take place in tandem, their individual events happening at the same time with Gen 2 & 4 taking place a little bit later. This pattern of games happening close to one another then starts to slow, with Pokemon Black and White happening even later and their sequels, Pokemon X & Y, after that.
While there are no concrete dates offered, it at least provides a framework (albeit a rather unstable one) to understand the chronology of Pokemon games. However, problems arise around Pokemon X & Y with the introduction of Mega Evolutions in the franchise. It’s here that the timeline is believed to split, and as a result, games that feature Pokemon using Mega Evolution take place in a reality that is parallel from the first five generations of games.
If games with Mega Evolution take place in a different timeline this also means that Gen 6 and 7, while part of the core franchise, move into a separate timeline from the one that is used for Gen 1 through 5. With this understanding, fans can begin to see a branch in the Pokemon timeline that also affects Pokemon Omega Ruby, Alpha Sapphire, and both the Pokemon Let's Go games. Similarly, Pokemon Sword and Shield may then also take place in a separate timeline, one where Ultra Beasts have been recorded, but instead of Mega Evolutions, there are Dynamax and Gigantamax Pokemon.
The good news about this is that Pokemon Brilliant Diamond and Shining Pearl seem to return to the original timeline. While they have some feature changes from the original Diamond and Pearl, the lack of Dynamax Pokemon as well as Mega Evolutions in Brilliant Diamond and Shining Pearl point to a change. This could also mean that Pokemon Brilliant Diamond and Shining Pearl are setting a precedent and trying to establish which of the timelines Pokemon Legends: Arceus will take place on.
When Does Pokemon Legends: Arceus Take Place?
If Pokemon Brilliant Diamond and Shining Pearl do indeed fall on the original timeline, and Pokemon Legends: Arceus will follow suit, then dating the game becomes a bit easier. Pokemon Legends: Arceus’ fans should then expect to experience Hisui as it was probably between 100 and 500 years ago in the Pokemon timeline. How early or late in this 400-year span will likely come down to a couple of different factors, with one specifically focused on Poison-type Pokemon.
If Pokemon in Pokemon Legends: Arceus can learn the move Toxic, then the game will take place 400 years ago or later. This is because the Pokemon move Toxic was canonically created by a ninja 400 years in the franchise’s past. This might be a somewhat obscure fact, but it could be the ultimate determining factor for when Pokemon Legends: Arceus takes place.
Similarly, the possibility of the dual Ghost and Dark-type Pokemon, Spiritomb, being present in Pokemon Legends: Arceus at the Hallowed Tower could also help date Arceus. Spiritomb was first sealed in the tower 500 hundred years ago by the time players come across it in the Sinnoh region. If the Hallowed Tower is present in Pokemon Legends: Arceus with Spiritomb inside, then the game takes place no earlier than 500 years in the past, but if not, then the opposite is true. This would make the Hallowed Tower the second of two major markers for understanding when in the timeline Pokemon Legends: Arceus takes place.
There of course is still the possibility that both of these appear, which would suggest that Pokemon Legends: Arceus takes place in a range between 400 and 100 years ago in the timeline. The visual style of the game and the technology available seems to point close to 100 years, but the name of the Hisui region is something to consider. The complete name change of a region is no small feat, and for Hisui to become Sinnoh, a major event is likely to have happened. With the inclusion of Pokemon like Shaymin and Darkrai alongside Arceus, players will likely experience a lot more than Noble Pokemon and Clans when Pokemon Legends: Arceus releases.
Pokemon Legends: Arceus releases for Nintendo Switch on January 28, 2022.