Oyvoyvoyv, the primary bad assumption being made here is that Twilight Princess follows the timeline of the other Zelda games, which it does not appear to. As near as can be told, it rewrites the history of the Imprisoning War wherein Ganon is sealed away. The Imprisoning War being the Ocarina of Time series of events where Ganondorf was sealed away by the Sages after he is defeated by the Hero of Time.

The time frame in which the Skeleton Knight dies has to be very specific. I'll lay out my reasoning for assuming what I assume.

Firstly, there is only one Imprisoning War, only one case in which Ganondorf was sealed away specifically by the Sages instead of just being out-and-out killed. This was handled different in Twilight Princess, in which there appears to be no way to access the Sacred Realm and the Triforce is never actually named. Ganondorf receives the Triforce of Power (or the Power of the Gods, as it's called in TP), but it's never clear as to how he got it.

The events in the backstory of Twilight Princess are analogous to those that happened in the Imprisoning War in Ocarina of Time - Ganondorf is sealed away at the height of his power after being defeated (in OoT by Link, in TP by someone we never see) and chained down (in OoT by Zelda, in TP by someone we never see). The events begin to diverge when they simply try to execute him instead of sealing him away, at which point he wrecks everyone's shit.

Anyway, I'm rambling. The operative assumption for my idea is that the Imprisoning War in TP and the events of OoT are actually two different versions of the same events, which is to say they're two tellings of the same story. We're looking at two legends, distorted in different ways.

Since Ganondorf is sealed away in the Imprisoning War, it seems that he has to have fought some equivalent to Link, otherwise he couldn't be defeated out-and-out. Enter the skeleton knight, who not only teaches Link the most powerful moves in the game, but out-and-out states that they are of the same blood, and whose Twilight/Sacred Realm form is the same as that of Link himself.

Evidence from throughout the game suggests that the Skeleton Knight died during the Imprisoning War, and many of his soldiers died alongside him. There is no mention of another war in Hyrule's history, and the declining state of their military only seems to support this. It stands to reason, then, that this Skeleton Knight was previously a flesh and blood person who fought in the wars against Ganondorf and died alongside many of his men.

Do we have reason to believe that the Skeleton Knight, in life, died fighting and defeating Ganondorf? No. That's not even directly implied. We do know, however, that he was there at the time, that he was a Link, and that he died in combat. We also know Ganondorf was defeated, and that while he has the Triforce of Power he's never been defeated by anyone who didn't wield a piece of the Triforce in return.

Trying to figure out how the Skeleton Knights knows those songs - legacy songs which relate to prior adventures of Links - is probably futile, because if Twilight Princess retells the story of Ocarina of Time then all bets are off. For the Ballad of Gales, though, that's easy enough: the King of Hyrule used to lead the sages in song, as established by Wind Waker, and it stands to reason that Link would have heard some of it.

Is it watertight? Lord no. Not even close. It's a conclusion drawn from disassembled bits and pieces and requires the assumption that Ocarina of Time, in the Twilight Princess story, didn't happen the way we had previously experienced.

But it does explain who the Skeleton Knight is, why he has so many parallels to the current Link, and why his spirit wouldn't rest until Ganondorf was killed.

That was a great post.

Just one tiny thing though. He couldn't rest before he had passed on his knowledge to someone who could perform it, not before Ganondorf was killed.

See, that's what I get for not playing the game for two years.

I think it's time for another playthrough, I do.

wasn't sniper wolf a woman?

 She also played the wolf in Okami.  Not too many wolves vying for jobs in the video game realm.  She's kind of the industry "go to" girl.

Hmm very interesting. Why I love the Zelda series. Always connects but have to think to find it haha. Oh I need to replay this again.

i haven't played the game in a while but the skeleton once said something like: "i accepted my duty as the hero" and then something like but not exactly "now that my skill are passed i can finally rest"

Khuutra's story seems like an idea for a new type of Zelda game, warrior knight Link leading an army of Hyrulians against the army of Ganondorf.... ;)

Hell, I'd play it. I'd play its brains out.

The thing about Zelda games is that there is no solid history or lore, and the games are almost always only vaguely related (except in the cases of direct sequels such as Majora's Mask). It is implied that the skeleton knight is a Link from a previous generation. Which one specifically is completely irrelevant, and there certainly isn't any solid answer. As with pretty much all Zelda games there is no direct thought out correlation so much as a vaguely implied lore.

Zelda isn't a story based series. Miyamoto and his teams have always focused on making incredible gameplay, locations, and immersion and the story is an afterthought, merely something to add context to the actions. As such the series isn't tied together in the way Metal Gear or even Metroid is. All you have is a vague lore, and that's all it's meant to have.