Beyond the Long River

Side effects of an empathic link with Thranduil may result in:

-Grumpiness
-Agitation
-Hyperawareness
-Loss of temporal awareness
-A veteran's paranoia
-Occasional sour or depressive moods for no apparent reason
-Magpie-esque attraction to shiny things
-The desire to muse about the good old days
-A distaste for the direction South
-The attitude that everything is a war and the passengers are an army
-Militant protectiveness over your loved ones
-Warm fuzzies when you see Legolas
-Not being a happy drunk anymore
-GUNS ARE DEVICES OF EVIL AND DARKNESS!!! AND MORDOR!!!
-The feeling that you are a Disney princess (unless you are one, then that's normal. we've had those.)
-Attempts to communicate with the birds in the gardens
-DO NOT TOUCH THE HAIR
-Sudden disappearance of sex drive because why would you desire to sleep with someone besides your wife?
-Thinking you have a wife
-Because let's face it, the vast majority of these characters don't
-Seriously don't touch the hair, that's just too invasive
-Responding to minor threats like a Navy SEAL jumping on a terrorist
-Or your non-United-Statesian equivalent of a Navy SEAL
-Or a Scotsman jumping on another Scotsman
-SHINY THINGS aw yis diamonds ARE a girl's best friend
-Punch Eric Northman in the face

STAGE TWO

Jadzia Dax: 1
Morgana: 1, 2
Mordecai: 1, 2
Heather Mason: 1, 2
Bail Organa: 1, 2
Sansa Stark: 1, 2, 3, 4
Catelyn Stark: 1, 2, 3, 4
AM: 1, 2

STAGE THREE

Arya: 1, 2, 3
Sauron: 1, 2, 3
Legolas: 1
Fili: 1, 2
Kili: 1, 2
Nill: 1, 2
Robb: 1, 2
Sulu: 1

What we know of Thranduil's background is fairly sketchy, so here are my attempts to fill it in. The framework of this is canon. The details are not. Very much a WIP.

First Age

Thranduil, son of Oropher, is roughly of Dior's generation. Therefore, he was born during the lives of Thingol and Luthien, but was quite young during that whole mess with the Silmaril bride-price (F.A. 466). He was born during the Long Peace in Beleriand, probably around F.A. 410. He, like most of the elves of Doriath, lived in Menegroth with his parents. Oropher and Mrs. Oropher were fairly traditional with regards to marriage and kids, so they had married young and recently (by elven standards) when they had Thranduil. They did not have any others because the Long Peace ended shortly after.

He was present for Túrin Turambar's fostering (F.A. 472) as well as the murder of Thingol by the dwarves of Nogrod (F.A. 502). The first time he did battle was in the Battle of the Thousand Caves (F.A. 503) against the invading dwarves. The second time was during the Sack of Doriath (F.A. 506) when the sons of Fëanor came for the Silmaril. Both of these times, he was less than 100 years old--a very young adult. When Doriath was lost, he fled with the rest of the Sindar to the Havens of Sirion.

During the Third Kinslaying (F.A. 538), he escaped to the Isle of Balar with the few survivors.

He did not fight in the War of Wrath, but witnessed much of its destruction. At the end of the First Age, he and his father made their home in Lindon. His mother was either killed during all these massacres or she sailed west after it was all over. Same goes for the vast majority of his extended family.

Second Age

Speculation: there is exactly zero canon evidence for this, but based on his actions in the Last Alliance, I believe Oropher was a deeply emotional person whose heart often overruled his head. It's possible that the beginning of the Second Age was as difficult a time for him as the beginning of the Third Age was for his son. While in Lindon, he became bitter and reclusive, and the loss of most of his family left him with a degree of emotional dependence on his son. Thranduil handled this with grace, since there was a lot of love between him and his father, but it made Lindon a trying time for him as well. Oropher absolutely hated being ruled by the Noldor and languished for some time before he and Amdir started to get together like old war buddies. They had ideas, took their time planning and making arrangements and connections, and eventually enacted a plan to leave Lindon and try to find their long-lost kin in Rhovanion.

They packed up their sons and whoever else would come with them and headed east. This all pretty much happens as stated in the UT, with the headcanon addition of Thranduil and Amroth becoming good friends on the road. Oropher became much more emotionally balanced with the change, and he and Thranduil were both very happy among the Nandor. But as Sauron started messing stuff up, basically everyone in Middle-earth was feeling it. Probably around this time Oropher moved his people as far north as the mountains in Greenwood, trying to dodge the spreading dominion of Sauron.

It was in the Second Age Thranduil met an elf-maid. Love developed between them, and it was shortly before the Last Alliance that they decided to get married. When it was understood he would be going to war, the general assumption was made that they would wait till after he returned to have a ceremony. She had other ideas. The night before he left, there was a celebration to send off the warriors. During a dance, she pulled him off into the woods and jumped his bones right there, saying she didn't want to risk not being his wife for ever. He protested for about three seconds, since the ceremony was going to mean a lot to Oropher (the "joining of bodies" is the thing that legally marries two elves, and the ceremony is just something for the families), but gave up pretty quickly. Oropher was disappointed but not angry when he found out his son was married without his involvement, but managed to be happy for them both and proud of his new daughter-in-law as they set out to war.

Ah, back through the glen I rode again and my heart with grief was sore
For I parted then with valiant men whom I never shall see more
But to and fro in my dreams I go and I'd kneel and pray for you,
For slavery fled, O glorious dead, When you fell in the foggy dew.

The Last Alliance was bad times for everyone involved. After Oropher's death and Thranduil's ascension, several years of siege passed before Thranduil gave up the idea of commemorating his beloved father by sticking to his values and finally started cooperating with Gil-galad. Two-thirds of Thranduil's army died in that war, and Thranduil was not the only one to come away from it with some pretty serious PTSD (the war affecting him this way is talked about in the UT).

Third Age

After returning from the war, Thranduil was not in a great state of mind. He could not forget the horrors of Mordor or even stop thinking of them for very long. In his personal life, he was probably very difficult to live with for a very long time since the therapists are all in Aman. He was capable of doing his job (which, it should be noted, he learned how to do in Mordor, of all places), but very much had classic PTSD symptoms--unsurprising, since the Silvan elves took the most casualties of anyone in the war. Though his wife wanted children, he refused to have them, which placed a strain on their marriage. He began to change his mind after a long, long recovery, but when the Shadow appeared in 1050 his time and attention was taken up with moving his people northward and battling this new threat. He had no children till the Watchful Peace, when he finally started to be able to breathe and unwind again. He had at least two but no more than three kids.

With the end of the Watchful Peace came a rehash of the same battles his people had been fighting since 1050, except this time the Necromancer was openly waging war against Gondor, so it was pretty distressing. Still, the Silvan folk have real spirit and were undaunted, even merry during their hardships as food within the wood became scarce. They used their magic, as per The Hobbit, to protect themselves.

The wood-elves saw the sacking of Erebor from the eaves of the forest, but as they were a week's march away at best, they didn't even try to do anything about it.

Everything else is as laid out in The Hobbit.