- For the conflict of the same name mentioned in Fire Emblem: Mystery of the Emblem and Fire Emblem: New Mystery of the Emblem, see War of Heroes.
The War of Heroes was a pivotal conflict in the history of the continent of Fódlan. Occurring over 1,000 years before the events of Fire Emblem: Three Houses, the war was fought between the forces of the Divine Seiros and the forces of Nemesis, the King of Liberation. Along with the Ten Elites and the Four Saints, these legendary figures wielded the Crests and the Sacred Weapons Heroes' Relics to deadly effect in battle.
In Imperial Year 91, Nemesis was personally defeated by Seiros at the Tailtean Plains. The heroes subsequently became the founders and leading nobility of the Adrestian Empire, which at its height encompassed all of Fódlan. The Church of Seiros, which followed Seiros' teachings and worshiped the Goddess, also gained considerable and lasting influence over the continent.