Underworld

The Underworld (アンダーワールド) is the mysterious virtual world in which the Alicization Arc takes place. The Human World is where the Humans live in the Underworld, it's a perfect circle with a diameter that measures around 1500 kilometers.

It is divided into four empires: Norlangarth North Empire, Eastabarieth Empire, Wesdarath Empire, and Southacroith Empire. Its capital is Centoria, from where it is ruled by the Axiom Church and the four empires.

Norlangarth North Empire
Norlangarth North Empire (ノーランガルス北帝国) is the northern empire of the Human World in Underworld. Rulid Village is the northernmost village in this empire. Zakkaria is a town to the south of Rulid Village. Deusolbert Synthesis Seven is 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 Underworld.

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

Southacroith Empire
Southacroith Empire (サザークロイス帝国) is the southern empire of the Underworld.

Law System
The Human World is ruled under the Axiom Church who established the Taboo Index as a supreme law above all, and its objective is to ensue the pacifical live of people and the self reliance of the live within the human world. The fundamental statement of the Taboo Index is that one cannot lower the live of anyone without a reason.

Below the Taboo Index are the laws established in each one of the four empires, and below it are the rules that apply to certain places such as the Sword Academy.

Although this system rules the entire world, and has a good purpose, it is full of flaws that people had found to commit evil acts without breaking the law.

It was later revealed that it was actually created by Quinella when she created the Axiom Church to ensure that nobody would be able to find the secret to "level up" as she was doing, allowing her to gain control over the Underworld human residents

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. Underworld