[1] François held the title of 36th vicomte of Thouars (1525–1541).
The la Trémoille family, inheriting the county of Laval after the death of Guy XX of the Laval family, the last representative of that county's direct line.
This inheritance obliged the descendants of Anne of Laval, and of François de la Trémoille, to come to stay on the banks of the Mayenne occasionally.
In effect, a decree of the parlement de Paris dating to 10 March 1536 reunited Rochefort with his domain.
The royal officers, always attentive to conserving the interests of their master, were justified by the tenacity of the La Trémoille family, shown especially by a royal debt of 18 000 écus to the family since the battle of Castillon in 1453.