The White-Gold Concordat was the official name given to the agreement signed that ended the Great War of the Fourth Era. The Great War was fought between the human-dominated Empire and the Aldmeri Dominion comprised primarily of Altmer of the Summerset Isles. Although the exact cause(s) of the conflict aren't specified, the Elven Supremacist government, the Thalmor, as well as a few quotes throughout Skyrim suggest the Elves were the aggressors. The events of this occurred after the Oblivion Crisis (the events of Oblivion) and before those of Skyrim. The treaty was the only means to end the conflict for the Empire and heavily favors the Aldmeri Dominion, who would have otherwise crushed the Empire. Among its legislation was the outlawing of the worshiping of Talos, disbandment of the Blades and giving free reign to the Thalmor to move throughout the Empire and to hunt down any worshipers of this outlawed deity, and the persecution of the last of the Blades.
The Concordat has caused a great deal of resentment in the Nordic population of Skyrim, who feel angered at the ban of Talos worship and dishonored at the Empire's surrender. (For example, the Dragonborn, if he/she joins the Dark Brotherhood, Amaund Motierre will perform The Black Sacrament to kill Emperor Titus Mede II.) The treaty, though its terms are very unfavorable to the Empire, was initiated by Emperor Titus Mede II and agreed to by the Aldmeri Dominion due largely to the outcome of the Battle of the Red Ring in 4E 175, in which the Aldmeri army in Cyrodiil was completely destroyed by the Imperial army under Titus II. The Aldmeri accepted the treaty, knowing that continuation of the war would now require a significantly larger investment of time and money, and the Empire initiated the treaty knowing that, despite a temporary reversal in fortunes, the Aldmeri were in a position to eventually overwhelm the Empire - the Imperial army had suffered the loss of three entire Legions during the war (one in the retreat from the Imperial City in the previous year and two more during the Battle of the Red Ring) in addition to the surviving portion having lost over half its men.
The Concordat's terms also included the cession by the Empire of a large portion of southern Hammerfell to the Aldmeri Dominion. Hammerfell, however, was unwilling to accept the loss of so much territory and continued to fight, forcing Titus II to officially release Hammerfell from status as an Imperial province in order to maintain the treaty, but not before allowing most of the legionnaires stationed in Hammerfell to be declared 'invalid', thus allowing them to continue fighting. The Redguards were eventually able to fight the Aldmeri to a standstill, leading to the Second Treaty of Stros M'kai in 4E 180, which dictated a complete withdrawal of Aldmeri forces from Hammerfell. Southern Hammerfell was, after five years of continuous warfare, left in a devastated state, and Hammerfell remained an independent province. It has been claimed that the Aldmeri stipulated the cession of southern Hammerfell to intentionally further weaken the Empire, knowing that the Empire would be forced to release Hammerfell as a province and create Imperial resentment among the Redguards, many of whom see the release by the Empire as abandonment.
A large tribute of gold would be paid to the Aldmeri Dominion, the Empire would give a large portion of southern Hammerfell to the dominion, the worship of Talos would be banned from the empire, the Blades would be forced to disband, and the Thalmor may have free reign in the Imperial Provinces, including Skyrim, to enforce the terms of the treaty.
- The name of the treaty references the name of the White-Gold Tower.