前史

1. Origins, structure, and basic meaning

• Structure: 前史, read ぜんし, is the earlier history preceding an organization's founding or a story's main action.
• Basic usage: 設立までの前史 covers events before founding; 物語の前史 covers background before the main narrative.

2. Common pitfalls and similar expressions

• Institutional background and narrative backstory
  • The reference point is supplied by the founding or main story; prehistory here need not mean a period before written records.