This timeline begins with what is known as The Sealing War. Judging by the timeline, I’d say that said war results in Hyrule’s decline, especially considering that the timeline has that labelled right beneath the event in question.
We then come to the Era of Light and Dark. Here is where the events of A Link to the Past occur. Most notably, this is where Ganon is revived. Following this come the two “Oracle games: Oracle of Seasons and Oracle of Ages (in that order no less). Once again, Ganon is revived. After this comes Link’s Awakening.
Hyrule then advances into the Gold era, where the Tri-Force using monarchy does…something. They…use the Tri-force I guess. People who actually play the game probably have an idea of what that one means, but I gotta say, this entry perplexes me more than anything else so far.
After that, Hyrule moves into the Era of Decline, where the first Zelda gets put into a mystical slumber (at least, that’s what I assume they mean by “the tragedy of Zelda I”).
Then come the events of the original NES Legend of Zelda game where Ganon is revived…again. Get used to seeing that sentence because, trust me, it’s going to come up a lot over the course of this series. Following that come the events of Zelda II: The Adventure of Link, where Ganon is not revived.
See, that wasn’t so bad now was it? This timeline is probably the shortest of the three. It only has a handful of games tied to it and there are only a few eras, making it pretty straight forward. We’ve still got two more lines to go, so you better not get too comfortable yet.
In part 4 we will dive into the second timeline where the Hero of Time is successful.
Sources
The Official Legend of Zelda Timeline Revealed. Sterling, Jim. Destructoid.com
The Official Zelda Timeline Now With Added Detail . Kotaku.com