When did the last of the High Elves leave Middle Earth ?

[Galin]

Originally Posted by Inziladun

Well, going back to the Letter #144 quote, Tolkien, at least at that time, was apparently certain that the High Elves encountered in LOTR were Noldorin.

He refers to them as 'Exiles', and 'part of one of the last main kindreds of the Eldar: the Noldor.'

Right, letter 144 was written to Naomi Mitchison in April 1954, where Tolkien says the High Elves met in the book are Exiles. In letter 154 to Naomi Mitchison in September 1954 Tolkien appears to equate High Elves with Eldar rather -- this is the reference that Hammond and Scull note in their Companion actually.

But rather than argue that Tolkien changed his mind later that same year (to possibly change it again some time later), I would rather suggest that two applications existed, for it is easy enough to imagine how High Elves came to be equated with Eldar (among the Quendi 'the Eldar were as kings' according to Appendix F). The term Eldar itself appears to have altered in reference as well.

And yet it's also easily seen how the same term could technically refer to those Eldar who had passed over Sea. For me the question becomes, how is it used in The Lord of the Rings proper? and need it be used consistently, even there?