okay do you see that? that's the original hyrule historia timeline published in 2011.
i was in the zelda community starting circa 2011 when it was published, though i was like barely a teenager at that time and not super involved in the fan community. but by 2014 i was writing fics, including starting my magnum opus in 2015, where i really started to dig into the lore of the series.
but i figured out something i honestly thought everyone else would have by now, yet i STILL see big zelda youtubers and loreheads saying that the timeline is confusing and that the downfall timeline in particular is confusing because it implies that any time the player dies as link, any number of new timelines are created.
THIS IS NOT WHAT THE HYRULE HISTORIA TIMELINE IMPLIES. it actually makes it very explicit that there's ONE circumstance wherein link dies and a new timeline is created:
i zoomed in to the most important part: that link loses AFTER challenging ganondorf to a final battle. this is the FINAL battle of the game. the new timeline splits only if link loses the FINAL battle.
and you might be thinking... okay, who cares? the timeline splitting is still fucked up and makes no sense.
BUT IT MAKES PERFECT SENSE. because this is the ONLY battle in oot where ZELDA is also present!!!
Because ZELDA is there IN THAT FINAL BATTLE with the OCARINA OF TIME.
When Zelda uses the Ocarina of Time, it seems to have a much more powerful, permanent effect. This is because she's implied to be the Sage of Time.
I know this is a bold-ish claim if you're a Zelda theorist and haven't heard this before, but there are seven temples, each with a specific theme.
You play through five of them. The Forest Temple, Fire Temple, Water Temple, Shadow Temple, and Spirit Temple. But there is also the Temple of Light which is housed in the Sacred Realm and houses the Triforce.
There is ALSO the TEMPLE OF TIME. The one right outside Hyrule Castle.
The sages of the others are known; Saria (Forest), Darunia (Fire), Ruto (Water), Impa (Shadow), Nabooru (Spirit), and Rauru (Light). That leaves only Time for Zelda.
Her control over time is far more absolute.
In the final cutscene with Zelda, here is what she says about how time travel will work:
"Thank you, Link. Thanks to you, Ganondorf has been sealed inside the evil realm! Thus, peace will once again reign in this world... for a time. All the tragedy that has befallen Hyrule was my doing... I was so young, I could not comprehend the consequences of trying to control the Sacred Realm. I dragged you into it, too. Now it is time for me to make up for my mistakes... You must lay the Master Sword to rest and close the Door of Time... However, by doing this, the road between times will be closed... Link, give the Ocarina [of Time] to me. As a Sage, I can return you to your original time with it. When peace returns to Hyrule... It will be time for us to say goodbye. Now, go home Link. Regain your lost time! Home... Where you are supposed to be... The way you are supposed to be..."
But notably, she doesn't play the Song of Time (which admittedly is from Majora's Mask) or the song to the Door of Time.
She sings Zelda's Lullaby. Which implies that this is a song that has ties to her as the Sage of Time.
Anyway, moving back to the issue of the Timeline.
My suggestion is that the reason for the Timeline split is because ZELDA split the downfall timeline off from the rest of the timeline.
I'm suggesting that Link died the first time around. They got very far, and it seemed that in the final battle Link would be victorious.
But instead, Link fell, shortly before defeating Ganon.
Zelda realized that this was the closest option that she and the other sages would have to seal Ganondorf, but they would be sealing him when he was still powerful. It would only be a matter of time before he broke out once more, but with Link dead, there was nothing else that Zelda could do. So she held Ganon back with her power long enough for the other sages to seal Ganondorf away. Not forever, but for long enough to give them a fighting chance to select a new champion.
But we never hear about OOT Zelda in the downfall timeline ever again after the Imprisoning War.
In fact, there is specific reason to believe that she disappears from this timeline, because Hyrule Historia goes out of its way to suggest that the Royal Bloodline weakens.
The only way to do that is that if the direct descendant of Hylia in an endless mother-daughter chain (aka the Zeldas of old) disappear, and instead they have to go with a more distant relative of Hylia to become the next Princess Zelda.
The implication here is that Zelda disappeared during the Imprisoning War. Seeing that the failure was because Link died, she used the Ocarina of Time to go back and give Link another chance at victory.
In my opinion, I think this is could have been when the identity of Sheik was actually born, because more would have to be different than just going back in time and doing the exact same things, and Zelda would only have control of her own actions. But that's a much less supported theory, aside from the line, "The flow of time is always cruel," which would have new meaning if she had watched Link die. But again: that line already has meaning in the game without this additional tidbit, and I don't want to focus on the least supported theory.
Anyway. Part of why I support this idea is that when Link travels through time, he travels in a closed loop. But when Zelda uses the Ocarina of Time, it creates fractures. She described it as such in her farewell speech: "Now it is time for me to make up for my mistakes... You must lay the Master Sword to rest and close the Door of Time... However, by doing this, the road between times will be closed... Link, give the Ocarina [of Time] to me. As a Sage, I can return you to your original time with it."
The way it's phrased implies that it's returning the sword and closing the door that will actually close the timeline -- but we can't actually PLAY that part, and we never actually see the door closed. The game ends the instant Zelda sends us back. I would argue that this implies that the closing of the timeloop is actually what ZELDA does. Not Link returning the sword and closing the door.
Additionally, the idea of losing access to the road between times implies that Zelda knows exactly how it works. While being the Sage of Time alone is enough rationale, I'd argue it would give this more narrative weight if she knows how this works because she's done it before. She knows Link will not be able to travel back once more, because Zelda has already fractured time once and knows she is unable to reach the timeline where Link died.
In a sense, Zelda abandoned that timeline to create a better future. That's why the downfall timeline is so dark. Not only because Link died, but because the Princess of Hyrule was lost to history.
Additional info-dumping about some other fun quirks of the timeline and how it actually makes perfect sense and a ton of the details line up in really clever ways:
The reason that the sages are random old men in Twilight Princess is because in the Child Timeline, Link never awakened Saria, Ruto, Nabooru, Impa, and Darunia as sages, therefore the 'sages' who died in Twilight Princess that we see in the Arbiters' Grounds cutscenes are random old men who probably were just priests of Hyrule Castle.
Link wasn't remembered as a Hero in the Child Timeline either, and Hyrule Historia implies that Link, still bearing the Triforce of Courage, was sent far away from Hyrule to avoid Ganondorf ever getting his hands on the full Triforce. This is why he ends up in Termina -- increased distance means that Ganondorf never got to rise to full power. Additionally, the OoT Link we see in Twilight Princess looks like a Stalfos -- given that so much of Majora's Mask begins and ends with Link exploring the woods looking for Navi, and Stalfos are what happens when an adult gets lost in the Lost Woods, it's implied that Link eventually turns into a Stalfos as an adult, on one last search for Navi.
Sorry for infodumping, it just drives me crazy that so many major Zelda Theorists are sleeping on such a graceful solution to the Timeline. If you'd just remember that Zelda has funky time powers and was literally right there in the final battle, where Hyrule Historia says right on paper that the timeline split actually happens (not just at any random game over screen), then it's pretty obvious what happened, imo.
(Feel free to send this to Zelda creators lmao I want to see this referenced in Timeline videos, but I do expect credit.)