Of the Elves who left Cuiviénen, some of the Noldor turned aside on the march to Valinor under the leader of Dan, calling themselves the Danas (LR/170-1, 175). They left the other Eldar early in the journey, before the travelers reached Beleriand. Later still, some of the Danas or “Danians” came over the Blue Mountains under the leadership of Denethor, where they encountered the Ilkorins, Elves who stayed in Beleriand along with their leader Thingol (LR/175). The Danians were called the “Green Elves” by the Elves of Beleriand, and settled in the region of Ossiriand (LR/114, 263).

The language of the Green Elves was influenced by the speech of the Ilkorins and became distinct from their kin who remained east of the Blue Mountains (LR/176). Their dialect came to be called Ossiriandic, while those of their kin was called East Danian (PE19/18) or Leikvian (LR/188). A version of this eastern dialect was adopted by the western tribes of Men later known as the Elf-friends (LR/194), becoming the language Taliska (LR/179, 196). After the fall of Beleriand, the Ossiriandic language was lost, and the language of their eastern kin faded and merged with the Lembi of the Hither Lands (LR/176).