The Fortress is a historical war drama centered on the Second Manchu invasion of Korea. The narrative focuses entirely on political maneuvering, military strategy, and the survival of the court during a siege. There are no identifiable LGBTQ+ characters or themes present in the film's plot or character arcs.

The Fortress is a historical drama set during the Second Manchu invasion of Korea in 1636. The narrative focuses on political and military strategies, the king, and his court. There are no identifiable transsexual characters or themes present in the film's plot or character arcs.

The film is a historical war drama primarily focused on male political and military figures. There are no significant female characters depicted engaging in direct physical combat against male opponents.

The film is a historical drama based on real events and a novel, depicting historical figures from 17th-century Korea. All major characters, who were historically male, are portrayed by male actors in the film, with no instances of gender alteration from their established historical or canonical identities.

The film is a historical drama based on a Korean novel, depicting real historical Korean figures from the 17th century. The cast consists of Korean actors portraying these figures, aligning with their historical and canonical racial background.