Oropher was one of the Sindar of Doriath, but after the War of Wrath he declined to depart Middle-earth as many others did, and instead went over the Blue Mountains with his household. He eventually ended up in Greenwood the Great, where Silvan Elves of Nandorin descent lived, and he was taken by them as lord. His capital was at Amon Lanc.
West of Oropher's realm was the realm of Lórinand across the Anduin, where Amdír, another Sindar, ruled over Silvan Elves. When Sauron returned to Middle-earth from the Downfall of Númenor and began to grow in power, Oropher's folk retreated north of the old Dwarf-Road, and later again north of the Mountains of Mirkwood, where they fortified themselves.
Before the War of the Last Alliance, Oropher and his folk left their capital at Amon Lanc and crossed Anduin to live with their kin in Lórinand. For another three times, he moved his people northward to Emyn Duir, the Mountains of Mirkwood. His retreat northwards was because of his desire to move "out of range" from the Dwarves of Khazad-dum.
Though he and his people had little to do with the other peoples of Middle-earth, Oropher understood that there could be no lasting peace until Sauron was defeated. Oropher answered the summons for the Last Alliance of Elves and Men but marched as an independent army with Amdír, or Malgalad the then King of Lórien. He joined with Gil-galad's forces as they marched down the Anduin to Dagorlad. Oropher's company was lightly armed.
In the Battle of Dagorlad, Oropher's company fought valiantly but he was slain with the greater part of his people when he accidentally called an early charge upon the enemy, without orders from Gil-galad. After Sauron was defeated, Thranduil, Oropher's son and heir, returned with the remainder of his people north back to Mirkwood. While beaten, their army was still large enough that the orcs hiding in secret in the Misty Mountains did not dare attack them.
- ↑ 1.0 1.1 1.2 1.3 1.4 Unfinished Tales, Part Two: The Second Age, IV: "The History of Galadriel and Celeborn, and of Amroth King of Lórien", Appendices: Appendix B, The Sindarin Princes of the Silvan Elves
- ↑ Unfinished Tales, Introduction, Part Three, I: "The Disaster of the Gladden Fields", Notes
- ↑ The History of Middle-earth, Vol. 5: The Lost Road and Other Writings, Part Three: "The Etymologies"
- ↑ Parma Eldalamberon, Words, Phrases and Passages in Various Tongues in The Lord of the Rings by J.R.R. Tolkien