Underworld

The Underworld (アンダーワールド) is the mysterious virtual world in which the Alicization Arc takes place.

Mythology
{{Spoilers| The following are a set of Gods that the Residence of Underworld worshiped within the Web Novel version of the story.

System
The god of life, one of the three god that create the Human World. The account, with unlimited territory transform capability, later used by Yuki Asuna.

Source
The god of sun, one of the three god that create the Human World. The account, with unlimited destruction and unlimited air-time, later used by Sinon.

Territory
The god of land, one of the three god that create the Human World. The account, with unlimited auto life recovery, later used by Leafa.

Lunaria
The god of moon

Vector
The god of darkness }}

The Original Four
The population of the Human World began around 70 Before HWC with 2 families of 8 Artificial Fluctlights each in a small village at the center of the Human World, the village of Centoria. Both of these families had 2 real Rath employees nurturing them, while the rest of the villagers were simulated with placeholder NPCs. The 4 members of Rath raised the first 16 Artificial Fluctlights to adulthood, teaching them everything from reading and writing to cultivation of crops and rearing of livestock to the morality of good and evil, however, one of 4 employees lacked ethics and unintentionally corrupted one or two of the children by passing down his egoism and desire for wealth and dominance to them. After the Artificial Fluctlights reached the age of 18 and started families of their own, the 4 humans logged out one after another by simulating an "epidemic".

The Growth of the World
After the «original four» logged out, the population of Underworld continued to grow, with the humans marrying when they were about 20 years old and bearing an average of 5 children, thus the 5th generation already consisted of 600 children, with about 400 still alive from the older generations. The children corrupted by the egoistic Rath employee became the ancestors of the future nobles as they secured their place as elites in the world. By the time of the 5th generation, the inhabitants of the Human World were already ruled by several lords, who, inheriting the egoism from their ancestors, earnestly continued expanding the land they owned, thus depriving the descendants of the non-corrupted first humans of land for cultivation. Most of the youth was then forced to work for the lords as tenant farmers, while some of them, who were not content with their social positions, set off from Centoria and traveled to the remote regions where they founded new towns and villages, like Zakkaria and Rulid Village, and thus acquired new land to cultivate.

Meanwhile, the lords that ruled over the capital held enmity towards each other, so there was a long period of time without any marriages between them. However, after some time, a political marriage happened between two families of lords for the first time. As a result of this marriage, a single daughter, possessing a higher level of egoism than any other lord in the world at the time, was born.

Axiom Church
The Axiom Church was founded around 30HWC (100 years after the creation of Underworld). At the time, the founder and head of the church was a girl named Quinella. Her Sacred Task was one not seen before in Underworld: “Sacred Arts Research”. She soon became very proficient at the Sacred Arts and had discovered many new rituals that people could use in every day life. At the age of thirteen, Quinella decided she didn't want to rule over the people as a lord or baron - she wanted to have absolute control, she wanted to become God. To do this, Quinella started doing “miracles” in front of people, predicting storms and healing sick and injured people in the name of "god". She told the people that a shrine to worship god needed to be built in order to perform even greater miracles, hence a large marble spire was erected in the center of town. This was the beginning of the Axiom Church. Years later when Quinella felt her life was coming to an end, she desperately tried to find a form of Sacred Arts that could manipulate her Life. Even at the verge of death, she still tried chanting various combinations of verses in the hopes of finding something that could help her. One fateful night, when she was just on the brink of death, Quinella discovered the Sacred Art: “Inspect Entire Command list,” and at the bottom of this list was the command that Quinella had been searching for, the one that would let her truly become God.

Human World
The Human World is where the humans live in the Underworld. It's a perfect circle with a diameter that measures around 1500 kilometers. The Human World is bordered by the Mountain Range at the Edge and connects to the «Dark Territory» via the «North Cave», «East Gate», «South Corridor» and «West Gorge».

The Human World is divided into four empires: Norlangarth North Empire, Eastabarieth Empire, Wesdarath Empire, and Southacroith Empire. The capital of all four empires is is their respective side of Centoria, from which the Human World is ruled by the Axiom Church and the four empires. Each empire is separated by the large «Immortal wall» (不朽之壁), which extends from the 4 corners of the Axiom Church and stretches to the Mountain Range at the Edge, thus limiting movement between the empires. An identification handprint is required to cross the Immortal Wall.

About 80,000 people live within the Human World, about 20,000 of which live within Centoria. The 4 empires together have about 2,000 soldiers.

Norlangarth North Empire


Norlangarth North Empire (ノーランガルス北帝国) is the northern empire of the Human World. The empire has fertile grasslands, deep forests and many lakes. Rulid Village is the northernmost village in this empire. Zakkaria is a town to the south of Rulid Village. Deusolbert Synthesis Seven used to be the Integrity Knight overseeing the Norlangarth Empire.

Eastabarieth Empire
Eastabarieth Empire (イスタバリエス帝国) is the eastern empire of the Human World. A defining feature of a resident of the empire is black hair.

Wesdarath Empire
Wesdarath Empire (ウェスダラス帝国) is the western empire of the Human World.

Southacroith Empire
Southacroith Empire (サザークロイス帝国) is the southern empire of the Human World. The Empire occupies an area that consists mostly of deserts.

Edge of Human World
Edge of Human World (人界世界の果て) is the border between the Human World and the Dark Territory.

Mountain range at the Edge
The Mountain range at the Edge (果ての山脈) is the mountain range that surrounds the Human World.

Dark Territory
Dark Territory (ダークテリトリー) is the country of demons. It houses goblins, orcs, etc. It is situated at the other end of the Mountain Range at the Edge.

Law System
All residents of Underworld are generally compliant to any law or rule that they regard as having authority, due to the effects of the Seal of the Right Eye. However, certain individuals, especially nobles, are able to circumvent the restrictions of the laws to satisfy their personal desires.

In the first decades of the Human World, the law system was passed down verbally from generation to generation in the form of parents teaching their children the basic moral rules that they should follow. Only after Quinella founded the Axiom Church, the first written law, the Taboo Index, was published.

Taboo Index
The Taboo Index (禁忌目録) is the absolute law in the Human world that was created by the Axiom Church to ensure Quinella's all-encompassing rule as well as to bind the masses with a sense of moral that suited the church's convenience. This rule system covers all crimes and their respective punishments, as well as prohibits actions that bring harm to other humans and limits hunting and storing food, as the world has limited resources.

Background
Quinella became uneasy that there was a chance that people in the remote regions who have lost their parents before receiving guidance on ethics from them might discover the secret behind the increase in System Control Authority and, if they possessed the genes of nobles, they might follow their desires to such an extent that, by murdering people around them, they would soon over-rank Quinella in System Control Authority. Thus, to reduce the possibility of that happening to the minimum, Quinella published the first edition of the Taboo Index and ensured that every town and village in the Human World would get a copy. All parents were then tasked to teach the children in the settlements to abide by her law as soon as they learned language.

Over time, Quinella revised the Taboo Index, adding new clauses that helped people with everyday life by restricting access to swamps that were the source of endemic diseases, listing plants that negatively affect livestock etc., in other words, anyone who followed the Taboo Index would not experience any problems and thus removing the need for people to think for themselves and to question the rule of the Axiom Church.

Known Clauses

 * 1) 1st chapter, 1st passage, 1st paragraph: Loyalty to the Axiom Church.
 * 2) 2nd clause: Unless another clause applies, one shall not intentionally reduce the Life of another person.
 * 3) One may not claim items that belong to others without permission. This clause only applies to stealing from humans.
 * 4) All children must be taught the clauses of the Taboo Index.
 * 5) 1st chapter, 3rd passage, 11th paragraph: Not anyone is to go beyond the Mountain range enclosing the edge of Human World.
 * 6) One cannot kiss another person's lips (likely unless they are married).
 * 7) One may not enter swaps that are deemed to be the source of diseases.
 * 8) One may not hunt more animals than permitted.
 * 9) One must not abandon their Sacred Task during work days.
 * 10) One may not take up too many tasks.
 * 11) One can only hunt animals if they have the Sacred Task of "Hunter".
 * 12) Deliberately destroying items that are sold in the shop is against the Taboo Index.
 * 13) It's against the Taboo Index to not pay for an item if it was broken accidentally.
 * 14) If the owner excuses a person for accidentally breaking an item, it would not be breaking the Taboo Index.
 * 15) One may not run away after committing a crime.
 * 16) Deliberately destroying goods that belong to others is against the Taboo Index.
 * 17) Obstructing the nobles' right to judge is not allowed.

Other Laws
Aside from the Taboo Index, all empires have an «Empire Fundamental Law» (帝国基本法). As all crimes and punishments are covered by the Taboo Index, the empire law is largely made up of conventions concerning the masses’ class system, in other words, the rights of the nobles and the rights of the commoners. The law guarantees the 4th class and higher nobles the right to judge lower ranked nobles and commoners, usually by cutting down their wages, though younger nobles tend to resort to physical punishment as well. This law was likely established by Quinella when she appointed the lords of the land as nobles in the name of god to secure their support.

Each village also has its own set of rules, for example, Rulid Village’s standards, and certain institutions, like the Sword Mastery Academy, also have their own regulations which hold as much power as the higher laws, however, in case of conflict, the higher laws take priority.

Dark Territory
There are virtually no known laws in the Dark Territory, though generally one rule is followed above all else: the weak shall follow the strong. As such, if one's leader is to perish, the one to succeed him would be the next strongest, under him. This is shown when the Leader of a group of Goblins was killed by Kirito, and immediately after, one of his subordinates stepped up to take his place.

Sacred Tasks
A Sacred Task (天職) is a lifelong occupation assigned to each individual in the Human World. Most people are assigned their Sacred Task at the age of 10 during Spring, with very few exceptions, for example, the children at the Axiom Church who can receive their Sacred Task even at the age of 5 while a child who is very gifted in Sacred Arts may have their Sacred Task postponed to allow them to train their talent. A Sacred Task is usually assigned by a village chief, the ruler of a town, a high-ranking noble with their own territory or a minister from the Axiom Church - the people in charge of the area where the child was born.

The Sacred Task assigned to a person the first time cannot be chosen by the people themselves and, once a Task is assigned, it is impossible for even those who assign the Tasks to revoke them. However, certain tasks can be changed if the person is promoted, for example, a village guard may become a sentry in a local town, a student at the Sword Mastery Academy, and even an Integrity Knight in the end, if they meet certain requirements. Additionally, if a Task is completed (this only applies to Tasks that have an end), the person may choose their next Sacred Task themselves.

In practice, the eldest son of each household is usually given the same Sacred Task as their father: a tool shop's owner's son would continue working in the shop, a guard's eldest son would become a guard and a village chief's eldest son would succeed them as the next village chief. For farmer households, this standard usually applies to their daughter, second and third sons as well, though there are exceptions. People who are assigned Sacred Tasks that do not provide a source of income are given a wage from the village's or city's vault.

Once a Sacred Task is assigned, a person is only allowed to rest from their job on rest days and may not travel in a way that would prevent them from working on their Sacred Task, meaning that mostly only traders could travel long distances, if it is part of their Sacred Task, while an average villager would only be able to travel if it was possible to return to their Sacred Task by the next workday.

Certain Sacred Tasks also have certain benefits, for example, a person who is assigned to be a guard is assigned a real sword to use and may spend time practising their sword skills. Although it is possible for someone to help others with their Sacred Task, it's against the Taboo Index to "have many Sacred Tasks".

Language
There are 2 known languages within Underworld: the Common Tongue and the Sacred Tongue.

Common Tongue
The Common Tongue is the main language used for writing and speaking in Underworld. It is the equivalent of the Japanese language in the real world, though the language is supplemented with a few words borrowed from other foreign languages. However, the major difference from its counterpart in the real world is that only about 1000 kanji, about the equivalent of 30% of JIS Level 1, are used in Underworld, while other words and most names are written in kana. Although the same language is used throughout the Human World, several accents do exist.

Sacred Tongue
The Sacred Tongue is the name given to the English language, though supplemented with a few words from other languages, by the residents of Underworld. This language is regarded as a sacred language used to ask the gods for miracles and is not considered as having any special meaning by the average resident, except for those who study the language for Sacred Arts. The language is mostly used in chanting the verses for Sacred Arts and written in system windows, like the Stacia Window, though a few names are also derived from this language, for example, the Gigas Cedar or the Dark Territory. The language can either be written in the English alphabet or in katakana for easier reading.

Calendar

 * For a list of events in Underworld, see Underworld Timeline.

The humans in Underworld have their own calendar, called the Human World Calendar (人界暦), which was developed by the Axiom Church. This calendar starts dating from about 70 years after Underworld was created, as the Axiom Church attempts to maintain the falsified history that it spread throughout the Human World. As the time flow in Underworld depends on the Fluctlight Acceleration rate set, the HWC cannot be aligned with the time in the real world.

Like its Japanese equivalent, the HWC has 12 months per year and, like the Japanese calendar, the names of the months are derived from the number of the month, for example, the equivalent of January is the 1st Month (一月), the equivalent of February is the 2nd Month (二月) and so on.

Code 871
It seems to be a code that will appear on an Underworld resident's right eye to prevent them from disobeying the law. When they have the thought to break the law, pain will be given to their right eye, and when they want to do so, their right eye would burst.

Trivia

 * Although the order of most names in the series use the Japanese order of the person's Last name then First name, as the setting of Underworld seems be the Middle Ages of Europe, the names of Underworld residents use the Western order of First name then Last name.
 * Only nobles and rich and/or famous non-nobles have the right to have a family name in Underworld.
 * The metric system is used in Underworld, however the names for the units have different names for the units, even though they have the same value. E.g. Meters are called Mel, kilometers are called kilolu, centimeters - centimel etc.
 * There are 8 elements in Underworld in published version, but 10 in web version