The alliance raid series for Final Fantasy XIV's Stormblood cycle was titled "Return to Ivalice" and took us to some iconic locations from previous Final Fantasy games. While Ivalice is a fictional country (or set of countries) in the Final Fantasy series, it is the location of only a handful of games: Final Fantasy Tactics, Final Fantasy XII, and Final Fantasy Vagrant Story.
By the nature of Final Fantasy games, the mere inclusion of the Royal City of Rabanastre, the Ridorana Lighthouse, and Orbonne Monastery doesn't mean the stories are linked at all. The Final Fantasy series loves to use transportable characters, bosses, places, and items all the time. Pretty much every Final Fantasy game has Ultima as an end-game boss, and most also include Omega and Shinryuu, crystals are a repeating trope in every one of the games, and players are almost always fighting against an evil empire.
While it isn't unheard of for games in the series to be set in the same world, it is unusual for them to be connected after-the-fact. With Final Fantasy XIV and the Ivalice trilogy, it's a little bit different. After all, prior to the Alliance Raid quest series in Final Fantasy XIV's second expansion, Ivalice was not a known location on the gameworld map.
We're about to delve deep into some Final Fantasy lore that includes spoilers for FFXIV Patch 4.5, so, consider this your spoiler warning.
However, running through the Garamysthe Waterway and the Clockwork City of Goug, it becomes obvious that Final Fantasy XIV's Ivalice is THE Ivalice. You encounter familiar bosses like Yiazmat and Argath Thadalfus. It also helps that the questline for the raid series is based on the story of Ramza Beoulve, the protagonist of Final Fantasy Tactics.
You could continue to think the Final Fantasy XIV version of Ivalice was simply an homage to some beloved older Final Fantasy titles (which is absolutely a thing the FFXIV team has done before), except for its "Zodiac Brave" story. The Trials of the Braves story, in Final Fantasy XIV, is a supposedly fictional chronicle of a set of heroes called the Zodiac Braves from Thavnairan legend. As part of the end-game relic quest set for Final Fantasy XIV: A Realm Reborn (the edition of the game to rise from the ashes of dismal MMO failure, aka game version 2.0), the Warrior of Light is tasked with re-creating events from those tales. In Stormblood (version 4.0 for those counting), we learn that the Zodiac Brave Story is a completely separate, supposedly fictional, account of a set of heroes from Ivalice.
The point of the Return to Ivalice raids is to prove the Zodiac Brave tale true. And, well, we do. In a rather spectacular fashion, the Final Fantasy XIV Warrior of Light encounters the spirit of Ramza Beoulve trapped in white auracite. Ramza, later joined by his Tactics companions, joins the fight against the final raid boss of the Orbonne Monastery. And saves the entire raid party's butts from annihilation. He and the Tactics cast later appear as spectral images to congratulate the WoL for finishing the fight against Ultima the High Seraph.
Which pretty much proves that FFXIV takes place in the future of the same world as Tactics, which also means its the same universe as Vagrant Story since those two are pretty much a package deal.
However, before players make it to the Orbonne Monastery, they meet with a very familiar Viera. Final Fantasy XII's Fran makes an appearance and sends the Warrior of Light on a ton of random fetch quests, all to prove a point to the naieve Princess that she serves. To make it more obvious that it is the exact same Fran, she's got the same costume design and looks like she stepped straight out of the Zodiac Age remaster.
Which means that Final Fantasy XII and Final Fantasy XIV are taking place at the same time. Given the context of several incredibly long cutscenes in the final raid quest series, it appears Fran and the Princess (almost definitely Ashe) are still working to kick the empire out of Dalmasca. Which would indicate that, somewhere out in the desert, Vaan is running around screaming "I'm the Hero of Dalmasca!" at random passersby. Or, at least, he was doing so in the recent past.
Sure, the idea that FFXIV and FFXII are taking place at the same time doesn't really hold up. The evil empire in FFXII is Archadia, and Vayne Carudas Solidor is the third son of the Emperor, Lord Gramis. And because all of the bosses and spirits shown in the FFXIV raids are connected to white auracite, which recreates the owner's fondest wish, it is entirely possible that all of the Tactics and Final Fantasy XII bosses are simply magical constructs created out of the minds of people who believed the Zodiac Brave story was the absolute truth. And the appearance of Fran, her hidden Princess, and the Dalmascan Resistance is all just coincidence.
However, in the last cutscene at the end of the Return to Ivalice series, we also witness the Empire conducting research in the Clockwork City amidst a sea of familiar Constructs, and the waters become muddied again. Because just who is it running the Imperial investigation in the Clockwork City? Noah van Gabranth. Final Fantasy XII's Judge Gabranth was born Noah fon Ronsenburg. So, having him appear in FFXIV as Noah van Gabranth wouldn't be all that unusual per Imperial naming conventions.
Hell, FFXIV's Gabranth even led the assault on Dalmasca years prior to the raid storyline, in armor that looks exactly like FFXII's Judge Gabranth. Theoretically, of course, Final Fantasy XIV could take place shortly after the events of Final Fantasy XII, but that would require Dalmasca to escape Imperial subjugation at the hands of Archadia only to fall right back into the hands of another evil empire, with several of the same key figures taking point in both empires.
Or the Garlean Empire took over the Archadian Empire, and Dalmasca never gained its freedom.
Or the Garlean Empire took over the Archadian Empire and then reclaimed Dalmasca, and we just so happen to have a new Princess leading the Resistance.
Regardless, Final Fantasy XIV almost definitely takes place in the same world as Final Fantasy XII, Final Fantasy Tactics, and Final Fantasy Vagrant Story. And might just be occuring at the exact same time as Final Fantasy XII.
Alternatively, this whole article might justt be an indication that I need to stop raiding and start sleeping.
Only time and Yoshi-P will tell.