How do we know when to use the passé simple in a text like this? Felt like it was quite random so wanted to understand the rule?

Question

Accepted Answer

Hi James,
The passé simple is the narrative equivalent of the passé composé so the rules will be the same, short and finished actions in the past.

She married = Elle épousa/ Elle se maria 
She was crowned =  Elle fut couronnée
She went back = Elle retourna

etc. 
In French, it gives an idea of depth in time which you don't have in English and is very hard to explain. 
Hope this helps!

Answer

To understand better, you need to understand the grammatical concept of "aspect" of a verb form. There are those three principal tenses: past, present and future. The tense tells you when an event happens.

The aspect tells you how the action happened in regard to the passage of time at that point. It expresses the relationship between the action of a verb and the passage of time. Aspects describe, regardless of when the action happens, whether it is:

Ongoing: an ongoing, or habitual action.
Simple: a one-time action, or an action not marked as to whether the results of the action are continuing.

Complete: This is a past action that has permanent or lasting results.

In French, the correspondence is this:

Ongoing past action: imparfait
Simple past action: passé simple
Completed past action: passé composé

Using the passé simple gives you a notion that something happened in a kind of time-capsule in the past with no connection to the present. These are events that might form part of a story (think fairy-tale). The passé composé tells you of things that happened in the past but have some relationship to the present. This distinction lends a kind of depth to narrations that would otherwise be absent.

In modern French, the passé simple has ceded its place to the passé composé with a consequent loss of distinction in aspect. It is now only used in a high linguistic register, i.e., in literature. But, again, this distinction is unfortunately quickly becoming a thing of the past.

The three dimensions of a verb -- tense, mood (imperative, subjunctive, conditional, and imperative), and aspect -- give the speaker a lot of freedom to express exactly what and how something happens.

Answer

English, by the way, has great tools to express different verb aspects:

I went to school and stubbed my toe.
I went to school stubbing my toe. (Doesn't make much sense, I know)
I was going to school and stubbed my toe.
I have been going to school stubbing my toe.

All of these happen in the past but carry quite different meanings. Think in terms of how the going to school action relates to the toe stubbing action. Think about whether one happened while the other occurred. And think about what it all says about whether the event happened once or repeatedly.