Port in W France at the head of the Loire estuary associated with a 1598 Edict (6)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
nantes
(Other definitions for nantes that I've seen before include "Loire city; its tolerant Edict" , "Port city in western France" , "French FC" , "French Atlantic port" , "City in Brittany" .)