This is the 615th most frequent French word.
fut
The word "fut" is the third person singular past historic form of the verb "être," meaning "was" in English.
Here, 'fut' is the passé simple form of the verb 'être', indicating a completed action in the distant past.
Il fut un grand écrivain reconnu dans le monde entier.
He was a great writer recognized worldwide.
In this sentence, 'fut' is used as the auxiliary in the passé simple to form the passive voice of the construction verb 'construit'.
Ce bâtiment fut construit il y a cent ans.
This building was constructed one hundred years ago.
'Fut' acts again here as the passé simple of 'être', used for narrative storytelling to describe a past event.