This is a translation of the official details.
Credit for the original translation goes to 春奈(Haruna)
Located in the north eastern-most edge of Regalia. Devoid of plant-life, this wide open land is overrun with monsters, spirits of the banished are also present. Banished by the Ancient Dragon, they've been cursed so they cannot cross the sea, most of the descendants of these fearsome and hateful beings end their lives here.
Ordinary people somehow managed to survive this extremely harsh environment; one of the "5 Travelers" was banished to this place for committing a heinous crime. Shidou has now undertaken the name "The Imortal King," organizing all of the banished into the country of "Endland."
With the demise of the Ancient Dragon, the curse has been lifted and this black corps that defied death is now crossing the sea into Regalia.
Immortal King Shidou
One of the original "5 Travelers" that first came to Regalia. Seeking immortality, he committed numerous sins against spirit kind. Thus, he was banished from Regalia. He is incomplete, but he will eternally suffer the pain of starvation and thirst. His heart isn't set on revenge but going after the Dragon Swords.
A Necromancer who serves the Immortal King.
He can manipulate the souls and bodies of the deceased.
He was once a sorcerer of high repute in Aledohr, his thirst for knowledge led him to use forbidden techniques kept in secret scrolls in the Gold Library.
He met with the Immortal King, and now serves him.
Immortal King's Knight Laurel
A former knight of Mysteria, her love of the Immortal King lead her to leave Regalia. The original Laurel perished long ago, so the Immortal King created another being with his magic. Having researched necromancy for a long time, he can now take the lives of others and preserve them with his necromancy.