On 13 October 1307, the forces of King Philip the Fair led by Esquieu de Floyrac, launched a surprise attack on the Temple, with the aim of capturing the Order's Grand Master, Jacques de Molay. Faced with overwhelming odds, de Molay tasked his advisor with hiding two relics in a vault beneath the Temple, a Sword of Eden and the Codex Pater Intellectus written by the Grand Master.
Unknown to the advisor however, Master Assassin Thomas de Carneillon used the assault in an attempt to obtain both artifacts. Eliminating the guards and taking both the sword and the book, de Carneillon was pursued through the fortress by de Molay's advisor, eventually facing his pursuer in combat. The Templar succeeded in recovering the artifacts from the Assassin, using the power of the Sword of Eden dropped by de Carneillon to incapacitate him, subsequently hiding the weapon and the book in the vault as instructed.
Four centuries later, François-Thomas Germain, a Sage and Grand Master of the extremist faction within the Templar Order, experienced a vision which led him to de Molay's vault, and discovered both the sword and the book. Reading through the Codex Pater Intellectus, Germain became obsessed with de Molay's ideals, and planned to recreate the Templar Order according to the vision written in the book. However, his radical ideas were not shared by all of the other members of the Order, which eventually led to Germain being exiled by the Grand Master François de la Serre. Germain subsequently gathered those sympathetic to his cause, orchestrating the murder of Grand Master de la Serre and the French Revolution to take control of the Order, and the people of France, following the fall of aristocracy.
Following the end of monarchy, the Temple became a prison for the royal family, housing King Louis XVI, Marie Antoinette and Louis XVII. In July 1794, Germain was confronted in the Temple's vault by the daughter of François de la Serre, Élise, and the Assassin Arno Dorian, who both sought Germain for the death of de la Serre. Germain used the Sword of Eden to battle the pair, but was eventually defeated when the artifact shattered, releasing a shockwave which killed Élise and mortally wounded Germain himself. Arno carried Élise's body out of the Temple, leaving Germain's corpse behind.
In 1808, Arno returned to the Temple with Napoleon Bonaparte, who decided to demolish the site. The pair entered the Temple's vault to recover Germain's remains, and buried them in the Parisian catacombs afterward.