When we arrived in Northrend back in 2008 at the start of Wrath of the Lich King, the undead Scourge was certainly our top priority. The Scourge has a significant presence in every zone except possibly Crystalsong Forest (though Icecrown Citadel looms large over it,) though I think the zone it probably has the least presence in (Grizzly Hills gives it a run for its money) is Storm Peaks, because, well, frankly, there's other important stuff going on there.
When we arrived, we got swept into a very convoluted quest chain that had us first helping some goblins deal with some rogue Vrykul, then helping said Vrykul deal with hostile giants, then working with said giants to uncover some of the mysteries of what the hell had happened with the Keepers of Ulduar. Ultimately, we teamed up with Thorim, and discovered the treachery of Loken, his brother (so to speak) who had been corrupted by Yogg-Saron. How long ago had this happened? Like, tens of thousands of years ago, if not more.
Ulduar's significance at the time was primarily that it served as the prison for Yogg-Saron, one of Azeroth's four Old Gods, but it was also the home of the Keepers, the leaders of the Titanforged on Azeroth, effectively making Ulduar the central command for the Titans' facilities on Azeroth.
The Keepers, if I recall correctly, were Thorim, Hodir, Mimir, Freya, Loken, and Tyr, and we would later find that Ra (known as Ra-Den to the Mogu,) Archaedas, Ironaya, and Odyn were also among their number.
Exploring Storm Peaks, we found that all Keepers' respective temples were abandoned, though Tyr's had been for a very long time. Gradually, we pieced together that Loken had been corrupted by Yogg-Saron, gradually capturing the other Keepers and placing them under a kind of mind control. Tyr had uncovered this treachery long ago, and fled south to what are now the Eastern Kingdoms, where Loken sent a pair of C'thraxxi to kill him, one of them succeeding in what would become Tirisfal (literally "Tyr's Fall"). Actually, the other C'thraxxi would attack Zul'Aman, and ultimately be defeated by Ula'tek, though only imprisoned (which is why we'll have to fight Kithix in the upcoming 12.1.5 patch). I believe Archaedas and Ironaya left either with Tyr or around the same time, both ultimately falling to... um... us, in Uldaman (whoops!)
Odyn likely left before all of this went down, because he threw a hissy fit when Tyr empowered the Dragon Aspects after their help fighting Galakrond, feeling that they should not rely on beings that weren't direct creations of the Titans. Ra had left after Sargeras defeated the rest of the Titans and a fragment of their souls found their way into the Keepers, overwhelmed and seemingly the only one who really understood what had happened. (Though this must have happened after Loken programmed the Curse of Flesh into the creation forges, as Ra-Den accidentally spread it like a computer virus to the Mogu).
Truly, the timeline here is a little tricky, especially because we don't really have a calendar system in Azeroth - the War of the Ancients was ten thousand years ago, and I think we have a handful of events that are put in relation to that (I think the War of the Satyr was a thousand years later, and the War of Shifting Sand was only a thousand years before the present day).
I actually don't remember if Ironaya and Archaedas were technically Keepers, or perhaps Watchers, which I believe is a lower rank.
But last we checked, here's where each individual is at:
Thorim should be at Ulduar, and was most recently seen helping Beast Mastery Hunters claim Titanstrike back in Legion. He seems fine.
Freya should also be ok at Ulduar, having been freed from Loken's madness in the raid and, like Thorim, helped us fight Yogg-Saron (unless we wanted to get the cool mount).
Mimiron is the rebuilt body of Mimir, who created the Mechagnomes (not to be confused with the playable Mechagnomes, who, like the standard Gnomes, were Flesh-Cursed versions of the original Mechagnomes, but just underwent cybernetic upgrades to try to return to their Titanforged roots). After he was slain I believe by Loken, his creations came and built him a new body that appears like a giant Mechagnome. Again, we freed him from Loken's subsequent madness and he helped us out.
Hodir is in the same camp, freed from the madness and back to his old business. The war between giants in Storm Peaks was always actually a little vague, but given that it was all started by Loken, perhaps it has settled.
Loken is dead. After Odyn left, Loken became the Prime Designate, and thus effectively leader of the Keepers, which meant that his death at our hands triggered the Re-Origination contingency, though once we fought hard enough to convince him, Constellar Alganon the Observer decided to abort the process.
Odyn was trapped by Helya, his vrykul protege, within his sort of false afterlife, the Halls of Valor, where he seemed to have used the knowledge he gained by trading his eye to Mue'zhalla to make a weird facsimile of Bastion and his own pseudo-Kyrians, the Val'kyr, which, ironically, Arthas would then copy himself to make undead Val'kyr out of the Vrykul whose loyalty he secured. While Helya committed great crimes, a lot of that was apparently revenge for Odyn being just an absolute fuckwad to her. With Helya's death in her own false afterlife of Helheim, Odyn was able to leave the Halls of Valor and announced an intent to go back to Ulduar, so we can probably assume he's there.
Archaedas is dead, slain by us in Vanilla before we knew all that much about the Titans or their creations in the first place. Same goes for Ironaya. Real failure to communicate here.
Ra-Den was captured by Lei Shen, the Thunder King, his heart used as a source of power to, I think, reverse the Curse of Flesh. After who knows how long deep down within the Throne of Thunder (wait, have I never gone and done that fight?) we fight him to knock some sense back into him. However, while fighting off the madness of N'zoth, Ra-Den is captured and taken to Ny'alotha, where he is corrupted and we are forced to kill him for real.
Tyr died in the early days of humanity, but in Dragonflight, we were able to reconstruct a body for him and bring him back to life. Tyr seems... very depressed, but he also does seem to remain the pro-mortal champion that inspired, among other things, the Knights of the Silver Hand.
So, that means that most of the Keepers are actually still alive. What, then, though, flows from that?
Well, there's a pretty strong implication that The Last Titan is going to see us find ourselves in an antagonistic relationship with the Titans and the Titanforged, as we've strayed pretty damn far from their original designs (those of us who are even descended from their creations) and the Titans' benevolence has seemed less of a given of late, especially when their "Ordering" of Azeroth starts to look like a kind of Black Empire with different aesthetics (why was the Worldsoul relocated from Harandar to the Titan-created Worldcore? Harandar certainly doesn't seem like a hotbed of Old God corruption).
Still, I'm not convinced the Titans as a whole, nor their creations, are going to be unified in a condemnation of the mortals of Azeroth. While Aman'thul seems to be the patriarch of the Pantheon and is likely sort of... patriarchal in his attitude. We know that he objected to incorporating the power of Life into Azeroth when Eonar was doing her work on it because it wasn't something they understood and could control.
Indeed, Aman'thul is the first of the Pantheon, and helped to "awaken" the other Titans. Did this involve forcing them into a form similar to his own?
Among the Keepers, Odyn seems by far the most likely to be an antagonist. I mean, the guy was kind of a douchebag even when we met him in Legion, and while he was friendly enough to us, he was deeply patronizing, and we know that he did awful things to Helya and also made some really shady deals, like trading his eye to Mue'zallah, who then passed it on to the Jailer.
Given Eonar's general embrace of Life as a power (also, the fact that her spirit was hiding out on a world called Elunara suggests she has some alliance/connection with Elune, who appears to be some sort of Life Goddess) I'm inclined to think she'll be on our side, and perhaps because of that, Freya will as well (as Eonar's most direct creation among the Keepers).
Tyr also seems likely to be on our side, as he seems the most willing to go against the grain and fight on behalf of mortals.
The other surviving Keepers, though... I could see going either way. I don't know if our efforts in Ulduar earned us any slack, but given that the Titanforged are kind of by design sort of rigid in their ways, I wouldn't count on them being friendly.