to codify, to put something into writing (said particularly of rules or decisions)

importance

South Pyongan (a province of North Korea)

North Pyongan (a province of North Korea)

oral history

historicism

historian

(Internet slang, especially anime and manga fandom) events or things from the past which one wants to whitewash/erase from history (due to it being embarrassing, poorly received, etc.); dark past

study of history

historic, historical / already-happened, past / former, old, traditional