A quelle Epoque se situe la venue d'Eriol en Eressea?

[Lomelinde]

Histoire externe (LT1:24, au sujet de notes indépendantes du The Book of Lost Tales) :

But what is important is that (according to the view that I have formed of the earliest conceptions, apparently the best explanation of the very difficult evidence) this was still the leading idea when it was written: Eriol came to Tol Eressëa from the lands to the East of the North Sea. He belongs to the period preceding the Anglo-Saxon invasions of Britain (as my father, for his purposes, wished to represent it).

Histoire interne (LT1:27) :

It is important to see, then, that (if my general interpretation is correct) in The Cottage of Lost Play Eriol comes to Tol Eressëa in the time after the Fall of Gondolin and the march of the Elves of Kôr into the Great Lands for the defeat of Melko, when the Elves who had taken part in it had returned over the sea to dwell in Tol Eressëa; but before the time of the ‘Faring Forth’ and the removal of Tol Eressëa to the geographical position of England. This latter element was soon lost in its entirety from the developing mythology.