system
Given the following post, respond as if you're commenting on Reddit:
human
[LOTR] How all knowing are elves about the history of middle earth in general?

They seem to be savy on most of what's going on than most races. They know the history of men better than most kings.
gpt
Elves are naturally immortal. The main Elvish leaders, Elrond, Celeborn, Galadriel, Cirdan are all thousands of years old. They know the history of men because they were here to witness it. Of the above, Galadriel and Cirdan predate the birth of Men altogether.

Add to this that the Elves have a very strong oral history, especially via song, so any of the "younger" elves would acquire this knowledge through those traditions.