Legolas' Entire Backstory Explained

The first king of the Woodland Realm in Mirkwood is an elven lord named Oropher. He leads his people as they relocate over and over again deeper into the woods. Eventually, though, he acknowledges the need to resist the spreading power of Sauron, and he leads an army to fight in the Last Alliance (that is, the gigantic war depicted in the opening sequence of The Fellowship of the Ring film).

The elves are successful in the war, and Sauron is temporarily vanquished. However, two-thirds of the Silvan army is destroyed in the fighting, and their king loses his life, to boot. In fact, many of their dead corpses, along with others who died in the fighting, are the ones that end up haunting the Dead Marshes that Frodo, Sam, and Gollum cross in The Two Towers.

When Oropher falls in battle, his son, Lee Pace — er, Thranduil (sorry about that) — takes over the reins and becomes the new king. Over the course of the Third Age that follows, Thranduil finds himself leading an ever-shrinking kingdom. This is partly due to the fact that the Necromancer and his minions have set up shop in the southern portion of the woods and are spreading out quickly. Eventually, dwarves — who are infamously unfriendly with elves — show up at the Lonely Mountain to the east, followed by Smaug the dragon, who turns the area into a desolate wasteland. Needless to say, while still strong, Thranduil's kingdom can hardly be said to be thriving at this point.