Fire Emblem.

Story is really superfluous. Even characters are disposable, as Etrian Odyssey, Pokémon or Shin Megami Tensei have proven.

Grinding, random encounters, and teenagers saving or destroying the world. Shin Megami Tensei ftw.

I also guess that American Civil War would be much too US-centric for Battlefield. These games are meant for a very large audience, and the Civil War is quite an obscure conflict outside the US.