Four nations

"neutral"

- Fire is the element of power. The people of the Fire Nation have desire and will and the energy and drive to achieve what they want. Earth is the element of substance. The people of the Earth Kingdom are diverse and strong. They are persistent and enduring. Air is the element of freedom. The Air Nomads detached themselves from worldly concerns and found peace and freedom. Also, they apparently had pretty good senses of humor. Water is the element of change. The people of the Water Tribe are capable and adapting to many things. They have a deep sense of community and love that holds them together through anything.

The Avatar World is divided into four separate nations: Water Tribe, Earth Kingdom, Fire Nation and Air Nomads; each nation specializing in one particular bending technique: Waterbending, Earthbending, Firebending, and Airbending respectively. In the time before the Avatar, the people bended the energy within themselves and thereby most likely lived as one.

Water Tribe


The Water Tribes are the nations of Waterbenders and their people. There are three tribes: the Northern Tribe, who live in the North Pole, the Southern Tribe, who live in the South Pole, and the Foggy Swamp Tribe, who live in the Swamp in the Earth Kingdom. Both the Northern and Southern Tribes are chiefdoms, ruled by Chiefs Arnook and Hakoda, respectively. The Swamp Tribe's political structure is unclear; it is possible that Huu serves as their leader in some capacity.

The Northern Tribe is strong with its Waterbenders, unlike its sister tribe. The Southern Tribe did not have as many Waterbenders (only one surviving Bender, which was Katara) and subsequently, fell under the attacks of the Fire Nation and was deeply affected by the damages that were caused.

They are occasionally referred to collectively as the Water Tribes. Generally, the Water Tribes do not mingle with the other nations, but seeing that a pirate salesman called out "Earth Nation! Fire Nation! Water Nation!", there are a significant amount of Water Tribe members also traveling the world.

Earth Kingdom


The Earth Kingdom is the largest and most diverse of the four nations, its people strong and proud, with some of them being Earthbenders. Their land is a massive continent in the eastern hemisphere and several islands. The Earth Kingdom is extremely diverse, having mountainous, forested, grassland, desert and man-conquered areas, including the vast megacity Ba Sing Se. Due to its people's bending ability, the Earth Kingdom could create magnificent structures out of stone such as the city Omashu.

The Earth Kingdom is run overall as a monarchy, the capital being Ba Sing Se. However, it is apparent that there are smaller regions and cities with their own rule, such as Omashu (which was ruled by King Bumi, captured by the Fire Nation and later restored again by Bumi).

It is sometimes referred to as the Earth Nation.

Fire Nation


The Fire Nation is the nation where Firebenders and their people live. It is located on an archipelago of islands located in the western hemisphere of the planet and is the most advanced of the four nations, with steam and gas power. It has a huge fleet of industrial war ships, and even recently adopted airships into its military.

The Fire Nation is also diverse in landscape, featuring many volcanic islands in its archipelago and on the mainland, as well as a tropical climate. It also has the world's most popular vacation spot, Ember Island.

The country is an absolute monarchy, and could even be called a dictatorship. In 0 ASC, the War was started by Fire Lord Sozin, using his country's advanced technologies. During the war, its people were oppressed and fed propaganda by rulers Sozin, Azulon and Ozai. However, in 100 ASC, the Fire Nation's conquest was ended and a new wave of peace began, with Zuko as the new leader.

Air Nomads


Air Nomads were the collective people of the Airbenders. Though the people of this nation are nomadic, the Air Nomads raised children and situated their central governments in four monastic temples located at various ends of the globe, two for males and two for females. The four Air Temples are located on small archipelagos that were Air Nomad land (which is most likely abandoned now) on the tip of mountains and, in one case, hanging under cliffs.

The Air Nomads are loosely run by elder councils, one male and one female. The people are extremely spiritual.

In 0 ASC, the Fire Nation executed a mass invasion and genocide of the Air Nomads, driving the nation into extinction save for the case of Aang, who managed to escape. It is sometimes referred to as the Air Nation in Fire Nation propaganda.

Trivia

 * The Fire Nation is the only nation commonly referred to as a nation out of the four as the Water Nation is the Water Tribes, the Earth Nation is the Earth Kingdom, and the Air Nation is the Air Nomads.
 * Also due to the propaganda at the Fire Nation schools the Air Nomads are referred to as Air Nation.