RE: Why did the elves really have to leave earth?
Alvin Eriol > December 5th, 2023, 10:16 PM
The Eldar, the Elves who accepted the invitation to make the Great Journey to dwell with the Valar in Valinor, and their children, acquired a longing for the Sea and to eventually go there once they were tired of Middle-Earth. This included the peoples of Teleri who remained when the Isle of Eressëa cast off and crossed the Sea without them, including the Nandor, Sindar, and Falathrim. Apparently any children of Eldar who were Elves themselves inherited the Sea-longing. Therefore, Legolas, whose father and grandsire at least were Eldar, could have a sea-longing awakened in him by approaching within sight/sound/aroma of the Sea.
It was the fate of Elves per the Creator Eru that as their bodies lived for ages, to Fade and become insubstantial if they remained indefinitely in Middle Earth. The Eldar furthermore had a latent if not active irresistible longing to go over the sea. The rising threat of Sauron motivated many lingering Eldar to take ship and depart at last, but others were either still young, or like Elrond, Círdan, and Galadriel, and certain others such as possibly Glorfindel, felt a duty to remain and serve. The Three Rings made this longing more bearable and easier to put off, but when the One Ring was destroyed, the Three were shorn of their power over Time and those very old Elves who had remained with Galadriel and Elrond, especially those Noldor who had come from Valinor in the self-exile, felt the weariness of Middle-Earth and the approach of Fading and therefore decided to go over the Sea after the fall of Sauron.