The Prophecy of the Dragonborn

The Prophecy of the Dragonborn is a legendary prophecy which tells of Alduin's return and his final fall by the hands of the Last Dragonborn. It is said this prophecy originates from an Elder Scroll, but it is also sometimes attributed to ancient Akaviri wisemen. This is how it goes:

When misrule takes its place at the eight corners of the world

When Brass Tower walks and Time is reshaped

When thrice-blessed fail and the Red Tower trembles

When the Dragonborn ruler loses his throne, and the White Tower falls

When the Snow Tower lies sundered, kingless, bleeding

The World-Eater wakes, and the Wheel turns upon the Last Dragonborn

Events foretold
"When misrule takes its place at the eight corners of the world"

This line describes the shattering of the Staff of Chaos. Staff of Chaos was a powerful artifact that could open doors to other dimensions. Jagar Tharn, the imperial battlemage, acquired it and used to imprison the Emperor Uriel Septim VII within Oblivion. Jagar Tharn broke the Staff of Chaos into eight pieces and scattered them all across Tamriel.

"When Brass Tower walks and Time is reshaped"

This line describes the activation of the "Brass Tower", also known as Numidium. Numidium was a giant construct made by the Dwemer to server as their God. His activation caused event called the Warp in the West which allowed for all possible outcomes to become true. The Warp in the West dramatically altered the nature of world, causing the Dragon Break, an unexplainable occurrence that forces a realignment of time and space in reaction to circumstances which render a normal continuity of reality impossible, in this case the activation of Numidium.

"When thrice-blessed fail and the Red Tower trembles"

The third part describes the fall of Dunmeri Tribunal by the hands of Nerevarine, a reincarnation of legendary Chimer leader, Indoril Nerevar. Back in the First Era, the Chimer and the Dwemer were waging war. Indoril Nerevar was the leader of Chimer forces and Dumac the dwarf-king leader of the Dwemer. The Dwemer were losing the war. In desperate act, Kagrenac, Tonal Architect and High Priest of Dwemer, tried to harvest the power of powerful artifact found deep in the Red Mountain, the Heart of Lorkhan, the Dead God. When he touched the Heart with his tools, he erased the entire Dwemer race from existence. Indoril Nerevar was seriously injured after his battle with Dumac and requested to hold a quick counsel with his three closest advisors, Almalexia, Sotha Sil and Vivec. The three swore to Indoril that they would keep the tools and study them, but never to use them for themselves. Soon after, Indoril Nerevar passed away. Some time after, Sotha Sil uncovered the secrets of Kagrenac's tools and found a way to turn himself, Vivec and Almalexia into gods. When the three turned into gods, Azura appeared, and cursed the entire Chimer race, creating the Dunmer or the Dark Elves. She then said that Nerevarine, the reincarnation of Indoril Nerevar, would come, and set things they are supposed to be. Not many people believed it, but it happened near the end of Third Era.

The fall of the Tribunal led to the Ministry of Truth,a giant floating satellite, which was suspended in the air by living god Vivec, crashing into Vivec City. Some believe this is the reason that the Red Mountain erupted. The eruption destroyed most of Morrowind and rendered it uninhabitable even for Dunmer.

"When the Dragonborn ruler loses his throne and the White Tower falls"

The first part of this line tells of Martin Septim's role during the Oblivion Crisis at the very end of Third Era. Emperor Uriel Septim VII is assassinated by agents of Daedric cult dedicated to Mehrunes Dagon, Daedric Prince of Destruction, called the Mythic Dawn. All heirs to the throne were assassinated too, except for one, illegitimate son of the Emperor, Martin Septim. He became the last Emperor of Septim bloodline, sacrificing himself and becoming the Avatar of Akatosh. In that form, he defeated Mehrunes Dagon, who tried to invade Tamriel, marking the start of Fourth Era.

The second part of this line tells of the Great War between Third Aldmeri Dominion and the Empire, more specifically, the sacking of White-Gold Tower after the siege of the Imperial City.

"When the Snow Tower lies sundered, kingless, bleeding"

The final event, before Alduin's and Dragonborn's return, is the Civil War in Skyrim. Current High King of Skyrim has recently been killed by Ulfric Stormcloak, the Jarl of Windhelm. This marked the beginning of the war. Many in Skyrim believe the Empire betrayed them with signing the White-Gold Concordat, a piece treaty between the Empire and Aldmeri Dominion. The treaty had several demands, among which was outlawing the worship of Talos, the hero-god of mankind. In life, Talos was known as Tiber Septim, the conqueror of Tamriel and the first Emperor of Empire of Tamriel. After his mortal death, combining the souls of two other mortals through process known as Enantiomorph, he ascended to godhood. This goes against the High Elven belief and is the reason why Talos' worship was outlawed. This also angered many Nords in Skyrim who still believed in Talos, leading to a war with the Empire.

"The World-Eater wakes, and the Wheel turns upon the Last Dragonborn"

The last line describes ultimate return of Alduin to Tamriel, leading to the Dragon Crisis.