Based on The Kingdom of the Woodland Realm Trilogy, Legolas is as old as Thranduil has been King--for 2900 years. Technically, that means Legolas was conceived on Thranduil’s coronation day. (FYI: Thranduil is not a morning person, by the way--he likes lingering in bed as most readers know).
Which is why by the time of the Battle of the Five Armies we know that Legolas is 2941 years old. He had to have been born in 41 Third Age--which interesting--in elven years--wouldn’t have been too long after the death of Oropher in the last year the Second Age that put Thranduil on the Throne after the death of his father.
And that’s why we celebrate Legolas’ Birthday and Conception in May--exactly nine months to the day of Thranduil’s coronation. Happy Aldúya (Treesday/Tuesday) Happy Lótessë (Flower-Month/May). Also fitting he would be born on Treesday as Tolkien describes Legolas as being as tall as a tree in The Lord of the Rings.
FACT: The reason I use Lasgalen (Greenleaf) rather than just “Greenleaf” is because there are two Legolas’ in Tolkien; the first was Legolas Greenleaf of Gondolin. Legolas is said to mean “Greenleaf” but it was also spelled in Nandorin as Laegolas, which, interestingly enough works well with his having a mother of Nandorin/danwaith descent. Correctly translated, Le-golas would mean “to thee-the foliage” or “heir to the foliage” or simply “Prince”. With Legolas Lasgalen, you are technically saying “Prince Greenleaf”--keeping the tradition of Legolas being a Prince of the Woodland Realm and keeping the moniker “Greenleaf” by making it part of his throne name (as in Thranduil Tárisil Oropherion) that has become legend in Tolkien/Middle Earth circles.
It is not sure if Legolas was named after the first Legolas (or as it is in my story Êlengolas, father of Thranduil’s mother Nimeithel), but I do know that what happens next in Book I, will have something to do with events that happen that do included the first Legolas--perhaps. 🤫