Final Fantasy XIV is set on Hydaelyn, a fictional world of diverse environments across multiple continents, focused on the region of Eorzea. Eorzea features four prominent city-states: Gridania, in the heavily-forested Black Shroud; Ul'dah, a trade-centric sultanate in arid Thanalan; Limsa Lominsa, a thalassocracy on the island of Vylbrand; and Ishgard, an isolationist theocracy in snowy, mountainous Coerthas. A land bridge links Eorzea to two other continents to the east, which have largely been conquered by the Garlean Empire. Other societies include indigenous tribes, such as Sylphs and Kobolds; Sharlayan, a scholarly city; and Ala Mhigo in eastern Eorzea, annexed twenty years prior by the Garlean Empire. Facing Garlean invasion, Ishgard withdrew from the Eorzean Alliance, leaving it defunct. The once-vibrant Mor Dhona region was devastated during the previous Garlean campaign.
Eorzean history is divided into prosperous "Astral" eras, and disastrous "Umbral" eras caused by great Calamities. The First Umbral Era marked the end of the age of gods. The Twelve, guardian deities of Eorzea, retreated from direct mortal contact. As society recovers from Umbral eras, new Astral eras begin. Under the hegemonic Allagan Empire of the Third Astral era, technological development reached its zenith, including aerospace construction. As each Calamity was linked to one of the six fundamental elements—air, lightning, fire, earth, ice, and water—the Sixth Astral Era was expected to last forever, but five years ago, the Garlean Empire triggered the Seventh Umbral Calamity.
Garlean scientists working on Project Meteor weaponized the lesser moon Dalamud. Under Legatus Nael van Darnus, they would annihilate Eorzea by crashing the moon, exterminating all opposition. The Alliance reunited in response, reviving their Grand Company militaries. Adventurers defeated van Darnus but could not stop Dalamud's descent. At the Battle of Carteneau Flats in Mor Dhona, Dalamud revealed itself as an ancient Allagan prison for the primal dragon Bahamut; his escape triggered the Seventh Umbral Calamity. Louisoix Leveilleur called upon the Twelve to imprison Bahamut, but failed; before he sacrificed himself to defeat Bahamut, he sent the adventurers "beyond the reach of time" for when they were needed again. Meanwhile, the Empire became paralyzed by a succession crisis as the elderly Emperor Solus fell ill.