The game takes place on the continent of Fódlan. The landmass is divided into three rival nations who are now at peace: the Adrestian Empire to the south and west, the Holy Kingdom of Faerghus to the north, and the Leicester Alliance to the east. At the center of the continent is the Garegg Mach monastery, home of the Church of Seiros and its Officer's Academy. The academy comprises three houses, each populated with students from their respective nations: The Black Eagles, Blue Lions or Golden Deer. The player assumes the role of Byleth, and may choose their name and gender. Once part of a mercenary group led by their father Jeralt, Byleth is offered a position to teach at the academy after an unexpected incident. As they start to teach their students, including Edelgard, Dimitri, and Claude, the heirs of their respective home countries, Byleth begins to see Sothis, a mysterious girl only they can see.
—Mageblaze14