Winter arrived in Eorzea a long time ago, as it has been revealed that Final Fantasy XIV: Heavensward was inspired by the A Song of Ice and Fire novels, which were adapted into the Game of Thrones TV series. There will be SPOILERS for Heavensward below, for the benefit of the influx of new players in FF14 that haven't reached the first expansion yet.
Heavensward is set in the land of Ishgard, where the Warrior of Light is forced to flee after the events of the post-story segments of A Realm Reborn. Ishgard is a land blanketed in snow, where the people have been warring with the dragons of Nidhogg's horde for centuries. The people of Ishgard are ruled by the Orthodox Church, as well as several noble houses. The Warrior of Light is the guest of House Fortemps during their time in Ishgard, as they seek to clear their name and bring an end to the Dragonsong War.
There are parallels between the story of Heavensward and the A Song of Ice and Fire novel series. It turns out the books actually inspired the game. Final Fantasy XIV Main Scenario Writer & World Lore Creator Banri Oda told 4Gamer (via Siliconera) that the A Song of Ice and Fire novels inspired the story of the Final Fantasy 14 expansion. The strategy game Tactics Ogre: Let Us Cling Together was also an inspiration for Heavensward.
According to Oda, it was the methodology of how these stories were made which inspired the design of Heavensward, as well as how they emulated real-life conflicts, with A Song of Ice and Fire referencing the War of the Roses, and Tactics Ogre referencing the Yugoslav Wars. In retrospect, it's easy to see how the elements from these different books and games influenced Heavensward, especially with its prominent noble houses, frost-covered lands, and dragons.
The strength of FFXIV lies in its storytelling and how it integrates the player into the world. There are many fans who contend that Heavensward is the height of the series, due to how it ties so many story threads from A Realm Reborn into one satisfying package. Then again, Shadowbringers is also cited as the high point for the entire Final Fantasy franchise. This is partly the reason why Stormblood is seen as the weakest expansion, as its story is much more scattered. Here's hoping that the upcoming Endwalker finishes the story of the Warrior of Light in a more satisfying way than Game of Thrones concluded things for its main characters.
Final Fantasy XIV: Endwalker will be released for PC, PS4, and PS5 on November 23, 2021.
Source: 4Gamer, Siliconera