Great War (Final Fantasy XV)

Great War was a war on the continent of Lucis in the Final Fantasy XV Universe that took place between 2/24–4/1 in M.E 725. It is called the "Great War" in the Archives entries in Final Fantasy XV.

Prelude
The Niflheim Empire seeks to conquer the world of Eos in their bid to recreate the glory of the ancient civilization of Solheim. Niflheim desires the powers the Astrals had bestowed upon Lucis and Tenebrae. Circa M.E. 606, Niflheim crossed the ocean to engage the Lucian-Accordian Allied Forces, and overwhelmed it with its magitek armors. Accordo surrendered and the Lucian king erected the Wall around the whole of the Cavaugh region that includes the Crown City of Insomnia, and took up a siege position. The conflict came to a standstill but Niflheim established its presence outside the Wall.

Having annexed Accordo and most of Tenebrae, Niflheim wants to claim Lucis's magical Crystal the kingdom is also using to project the impenetrable magical Wall across its realm. Upholding the Wall drains the king's life, accelerating their aging. After Ardyn Izunia entered Niflheim and established himself as chancellor, he proposed the creation of a magitek infantry. After Research Minister Verstael Besithia developed a way to mass produce magitek cores, the empire prepared to renew its full offensive on Lucis. By the 24th October of M.E. 724, Niflheim had overwhelmed Lucis with the newly mass-produced magitek infantry and surrounded Insomnia.

Battle
Prince Regis set out to Accordo to try and re-establish the Lucian-Accordian Alliance. He traveled with his royal mechanic Cid Sophiar, his Shield Clarus Amicitia, his friend Weskham Armaugh, and a renowned Crownsguard officer Cor Leonis. They fought in the front lines against the empire's new magitek soldiers, as Lucis sent out its forces to engage the empire. The empire breached the areas of Cleigne, Duscae and Leide. Though Regis and his friends made it to Accordo with the Royal Vessel, they failed to establish an alliance and Lucis was overwhelmed by the imperial might. Regis was forced to return to the Crown City as the army withdrew. King Mors pulled back the Wall to Insomnia's ramparts to strengthen it and halt the imperial advance.

Aftermath
Many areas previously shielded by the Wall were left vulnerable to imperial oppression and were destroyed, including the rich town of Keycatrich. Refugees flooded to Insomnia, but the monarchy's entry policy was strict. Cid Sophiar fell out with the royal household due to this and left Insomnia for good. Weskham, who hailed from the now-destroyed Keycatrich, settled in Accordo where he had befriended Camelia Claustra, the leader of an antiestablishment resistance force. Their friendship would help reestablish conciliatory relations between Lucis and Accordo. Niflheim occupied even more of the Lucian outlands and built new bases there. A period of peace followed.