The isekai genre is one of the most popular and defining genres of anime. In this genre, characters, usually teenagers from modern-day Japan, suddenly find themselves launched into another world where they have to go on an adventure in order to get back home.

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Some of the worlds where people end up in these series are just past versions of our own world, while others are video games or fantasy worlds. But several of them have a basis in real-life history, even when they don’t necessarily take place in the past. Here are 10 isekai worlds that have a basis in real life.

10 Ascendance Of A Bookworm

Our main character loves reading books and wants nothing more than to be transported to a world where she doesn’t have to do anything but read. When she dies following an accident and wakes up in a world where she’s five years old and books are hard to come by, she discovers that books are mostly kept for the elite and out of the hands of commoners.

She’s not actually that far off from what Japan—and much of the world—used to be like. Books used to be hand-copied, which made them more difficult to get and meant that most people didn’t have easy access to them.

9 How A Realist Hero Rebuilt The Kingdom

In How A Realist Hero Rebuilt the Kingdom, the hero Kazuya is transported into another world where he suddenly becomes the ruler of a kingdom when its king realizes he is competent and no longer wants to rule.

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Kazuya, who has been studying political philosophies, decides that he can handle this using Machiavellianism, which essentially means ruling with ruthlessness and cunning and not being honest with those beneath you. This means that the kingdom he has found himself in has some basis in 16th-century Italian culture, where Machiavelli lived and worked.

8 Fushigi Yugi

Miaka and Tamahome drawing swords and fighting side-by-side in Fushigi Yugi.

In Fushigi YugiMiaka finds herself transported through a magical book into an ancient Chinese city. While the city and the lands surrounding it are fictional, the story deals with four Chinese mythological creatures, each of which lends power to each of the four lands.

These creatures guard the four directions of the earth, and each also has associations with the four seasons, along with certain colors, numbers, elements, and virtues. These gods or spirits are considered guardians and deities and have historically been important in East Asian religions and cultures. In the series, they serve a similar purpose, though they are called by different names.

7 Inuyasha

Inuyasha is one of the most well-known and widely-watching anime of the last 20 years. The series follows a teenage girl named Kagome who accidentally falls down an empty well at the shrine her family runs. When she climbs out, she finds herself in feudal Japan.

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While the setting of the series is a real historical place and time in Japan, there are elements to the series that set it apart from the actual history. For example, Inuyasha is a demon, and, while demons were probably widely considered to be real in feudal Japan, they probably weren’t overtly attacking villages like they do in the series.

6 Overlord

Overlord is slightly different from the previous series in that it’s the one on this list that takes place not in a fantasy or historical setting, but instead in a video game. The main character is transported into an MMORPG called Yggdrasil where he has to battle his way through the game in order to find others like him who are trapped there.

Yggdrasil is a place of myth in Norse mythology and is essentially a giant tree on which all of the known worlds exist as branches. It’s a fitting setting for a video game where different worlds have to be explored.

5 Spirited Away

Chihiro-Haku-run-away-Spirited-Away

Spirited Away takes place in a Japanese bathhouse for spirits, but it’s based on a real-life bathhouse that Hayao Miyazaki remembered from his hometown growing up. He thought it was mysterious and wrote many stories about what happened behind its closed doors.

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The bathhouse is also partially based on some of the buildings in the Edo-Tokyo Open Air Architectural Museum, which is a park full of historical Japanese buildings, and a traditional Japanese inn called Notoya Ryokan. Miyazaki was very interested in making the bathhouse look as much as possible like a Japan of a bygone era.

4 The Vision Of Escaflowne

The Vision of Escaflowne follows a teenage girl named Hitomi who suddenly finds herself transported to another world when a boy fighting a dragon appears on the track at her high school. In this other world, called Gaea, she finds herself in the middle of a war between two kingdoms.

Part of the battle involves a mech called Escaflowne, which Hitomi has the ability to awaken. Gaea is essentially Atlantis, except it's been raised into the sky in order to keep it from sinking. Writer Shoji Kawamori was inspired by the country of Nepal. He felt the foggy mountains were the perfect setting for an epic story about fate.

3 Accomplishments Of The Duke’s Daughter

Accomplishments of the Duke’s Daughter's isekai plot is more or less revealed through the title. The title itself mentions a duke, which already tells us something about the setting of the series. Dukes and duchesses are staples of European monarchy and aristocracy.

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Dukes and duchesses are often royalty, and the title is usually passed down in a family. The series takes place in a past age in which technological advancements like baking food in ovens don’t yet exist and most commoners don’t get an education, meaning it likely takes place before the 19th century in a European country.

2 The Ambition Of Oda Nobuna

Many isekai series take place in historical Japanese settings, some of which are pretty fantastical, which makes sense since they’re being created in Japan. The Ambition of Oda Nobuna is one such anime. The series follows a high school student named Yoshiharu, who has found himself transported to the Sengoku period.

The series actually features a real-life Japanese heroic figure named Toyotomi Hideyoshi who was a warrior and politician during the Sengoku period. Part of the fun of this series is that Yoshiharu is obsessed with a video game about the Sengoku era, but his actual experiences interacting with people from that era are totally different, and there are ultimately differences that he can’t account for.

1 Aura Battler Dunbine

Aura Battler Dunbine

Premiering in 1983, Aura Battler Dunbine is the oldest example of an isekai series on our list and is actually probably one of the oldest of the genre. The story takes place in a fictional world called Byston Well, which is in another dimension.

The series is based on medieval Europe, but it is, of course, a fantasy version of it. In fact, much of its magic looks like the kinds of things people believed existed in those times: dragons, unicorns, etc. The big difference is that there are also giant robots called Aura Battlers which are used in battle.

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