Main cast is presented as military personnel and the story is about military operations.
Alternate name: War fiction
The first video game about Military fiction was released in 1982.
Note that games with war tag do not automatically become military fiction solely because the story itself may have little to do with actual military fiction. War tag only shows (part of) the setting, not the type of fiction. Nor are militainment or similar games always military fiction, though very likely are if they have any kind of story in them. Military fiction does not always involve wars in general.