Fire Emblem Warriors continent

The continent that appears in Fire Emblem Warriors is unnamed. It is a continent home to a few diverse locations, such as forests, volcanoes, gorges, and deserts.

Pre-Game
Long before the events of the game, there was a Divine Dragon who protected the continent. Soon, the Chaos Dragon, Velezark, unleashed an army of monsters known as Outrealm Fiends, as well as Fire Dragons. The two dragons fought, forcing the Divine Dragon to seal Velezark away with a Shield containing her power. After the battle, she went to the World Tree, where she spent the last few moments of her life, leaving behind two of her fangs in the form of swords, Enliron and Facinna, which could pierce through Outrealm Fiends with ease.

The two kingdoms, Aytolis and Gristonne, had a bad bond between them, which was eventually broken into a more friendly one.

Yelena and the King of Aytolis eventually had twins, Rowan and Lianna, while the King of Gristonne, Oskar, had a son named Darios. The King of Aytolis eventually died, while the trio of young royals became friends.

War of the Chaos Dragon
One day, the Chaos Dragon was close to being resurrected, releasing Outrealm Fiends and heroes and villains from two other worlds (one of which from two time periods), and seemingly killing Yelena. With the heroes of Ylisse, Hoshido, Nohr, and Archanea, the twins searched for Gleamstones. that were carried by five heroes from other worlds, and obtained the swords left by the Divine Dragon.

Darios eventually fell to the Chaos Dragon's power, and became possessed, while Velezark formed a temporary alignment with Oskar. Yelena was also alive, and planned to be a sacrifice to give the Chaos Dragon his full power. After Yelena was saved, Velezark betrayed Oskar and killed him as the sacrifice, giving him his full power. Velezark soon left Darios' body, killing him in an attempt to take the lives of the twins.

Afterwards, the heroes and the twin royals fought Velezark and finally destroyed him once in for all. This also forced the heroes to return to their worlds.

The twin royals were soon crowned as king and queen of Aytolis.

Kingdoms

 * Aytolis
 * Gristonne

Similarities to other Fire Emblem continents
The world of Fire Emblem Warriors takes inspiration from several canon continents of the Fire Emblem series.

Archanea and Ylisse

 * The Fire Emblem is a Shield with five orbs powering it.
 * The sacred sword(s) is made of the fangs of a Divine Dragon.
 * There is a Dragon's Table.
 * The desert coliseum bears a resemblance to Arena Ferox.
 * The main enemy dragon leads an army of Fire Manaketes.

Valm

 * There is a large tree that has a connection with the Divine Dragon of this world, similar to the Mila Tree.

Fire Emblem Fates continent

 * There are two opposing locations:
 * One is a gorge with a medieval Japanese castle, resembling Hoshido.
 * The other is a volcano with a medieval European castle, resembling Nohr.
 * Dragon Vein exist in this world.

Various Continents

 * There is a kingdom with a pair of opposite gendered twins, similar to Magvel and Zenith.
 * The Divine Dragon is allied with humanity, just like Archanea, Elibe, and Ylisse.
 * The Chaos Dragon takes inspiration from Medeus, Loptyr, Grima, and Anankos.
 * As noted by Robin, the weapons of this world do not break after enough use, as they do in Valentia and the world of Fire Emblem Fates.