Present tense vs past tense for known facts?

Question

Hi teachers/fellow learners, for the last sentence "où Le Débarquement a eu lieu en 1944" I was under the impression that for known facts we use present tense in French, but it turns out that passé composé is more suitable. Can you tell me more about this? Thank you so much.

Maarten Kamp · Accepted Answer

Ngoc, 
I think you may be confusing the use of present tense in historical narratives in French, with the everyday description of events. 
In this story, the ‘ present ‘ is one week after the visit to the Caen Memorial - this is the reference point from which everything is described.
She now wants to visit a place where something previously happened - with concordance des temps, these 2 things cannot be in the same tense, and as the event in the past is clearly defined and limited, passé composé is used for it.
Note that ‘ concordance des temps’ still applies in historical writing as well - not everything is in present tense. See 2nd link for a further discussion of historical tense usage.
 https://progress.lawlessfrench.com/revision/glossary/verb-tense-usage/la-concordance-des-temps-sequence-of-tenses 
https://www.lawlessfrench.com/grammar/historical-tenses/