One more word for it is 'past history'. The past history of a person, place or thing can be considered as its back story. If we are talking about a building, its past history like who built it, what it was used for in the past, any significant events that took place there, all form its back story.
A synonym for 'back story' could be 'background'.
Another word might be 'pre - history'. It refers to the events or circumstances that precede the main story or situation, much like a back story does. For example, in a movie, the pre - history of a character, which includes their childhood experiences, family background, and early life events, is their back story. This pre - history often shapes the character's actions and decisions in the main plot of the movie.
Prehistory is another word for back story. It refers to the events or circumstances that happened before the main part of a story.
Well, 'narrative' is another word for story. It's often used to describe a sequence of events or a tale.
A long tale. For example, when we talk about a very detailed and extended account of something, we can use 'tale' instead of'story' and 'long tale' to mean a long story.
Headline. A headline is often used to refer to the main or top story in a newspaper, magazine, or news website.
Tale. It is a very common word used instead of short story. Tales often have a simple plot and are usually passed down through generations orally or in written form.
Main character. A story usually revolves around the main character. This could be a person, an animal, or even an inanimate object in some cases. In 'The Little Prince', the little prince is the main character. He is the focus of the story, and all the events and interactions are related to him in some way.