.... wait, what?

[Beanamir of Gondor]

Perhaps someone else here has read the Histories of Middle-earth more closely, but I'm not finding the answer anywhere.

In his eponymous council, Elrond, in the middle of describing the battle of Dagorlad, pauses and sighs. "I remember well the splendour of their banners," he said. "It recalled to me the glory of the Elder Days and the hosts of Beleriand, so many great princes and captains were assembled. And yet not so many, nor so fair, as when Thangorodrim was broken, and the Elves deemed that evil was ended for ever, and it was not so."

Whoa, back up. Upon re-reading the section in the Silmarillion concerning the fall of Thangorodrim, we are told that among the host of the Valar "went none of those Elves who had dwelt and suffered in the Hither Lands," i.e. no Elf living in Beleriand at the time. So Maglor, who was pretty much raising Elrond and Elros at the time (if I'm not mistaken) wouldn't have gone to the battle, much less taken them with him.

Then even afterwards, when the Valar summoned them to depart Beleriand for the west, Maglor and Maedhros refused; we don't know anything about Elrond again until he chooses to be counted amongst the Eldar, a page later. But it seems doubtful that he would have seen the host of the Valar encamped, much less in battle, since his foster-father only snuck into their host once, and it was to steal a Silmaril. The indication is that some Moriquendi (Galadriel, Cirdan, and Elrond among them) never came to the summons, but just... stayed where they were.

Hmm. So is Elrond just speaking about the host of the Valar from stories he's heard, did he manage to see them encamped and just get the general idea... or is it conjecture? I'm irritated that he presents the information to Frodo and the Council as if he were there at the fall of Thangorodrim himself. (I'm also irritated with myself that until now I took it for granted that Elrond was at that battle.)

Silly Elves and their histories. Anyone?