The history of Tamriel is bloody and turbulent. There are six Eras of Tamriel, each denoting a significant time period and change.
The Dawn EraEdit
The Dawn Era is the Era in which time began and the world was created. It was a time of chaos and magic where gods walked Nirn. Elven history begins after the Cosmos stabilizes when Magnus leaves the world of Nirn and Lorkhan is condemned for creation of the mortal plane. It begins with the emergence of Anu and Padomay and ends with the Convention.
The Merethic EraEdit
The Merethic Era is the Era that begins when a linear timeline can be discerned. This Era begins in ME 2500;the earliest date to be recorded by King Harald's scribes, and goes backwards to 1E 1 (the first year of the first era). Some notable events of the Merethic Era include the construction of the Adamantine Tower (ME 2500), the exodus of the Aldmeri peoples from their ancestral homeland of Aldmeris and the settling of the vast coasts of Tamriel, and later the exodus of the "Nedic" peoples from the continent of Atmora, the ancestors of the Nords, who begin settling the northern coasts of Tamriel. The Era ends with the founding of the Camoran Dynasty in Valenwood.
The First EraEdit
The First Era is a very long Era which lasts for 2,920 years and is marked by a visible shift in power between the Elven and Human races, with the rise of the Cyrodiilic Empire and the Alessian Rebellion. The Second Era begins when Reman Cyrodiil III and his heir, Juilek, are assassinated, ending the Reman line of Cyrodiilic Emperors, and the Tsaesci Potentate Versidue-Shaie takes the throne. The most notable events of the First Era include the formation of the first Orsinium, the first kingdom of Skyrim, the first empire of the Nords, and the first "Empire of Man" led by Saint Alessia.
The Second EraEdit
The Second Era lasts 896 years, beginning with the death of the Reman dynasty at the hands of the Morag Tong, and ending with Tiber Septim's harnessing of the Numidium and bringing peace to Tamriel. The more notable of the events of this Era include the assassination of Potentate Versidue-Shaie and later his son Savirien-Chorak and all his heirs, ending the second Empire of Men and causing the Interregnum. This period was also marked by the Three Banners War between the Ebonheart Pact, Daggerfall Covenant, and the First Aldmeri Dominion over the Ruby Throne, while the elven necromancer Mannimarco ruled the Empire and worked with the Daedric Prince Molag Bal, who wished to drag the mortal plane into his own plane of Oblivion, Coldharbour.
The Third EraEdit
The Third Era is a rather short era which lasts 433 years (it is the Era in which the first four main entry Elder Scrolls games occur). This Era began when Tiber Septim united all of Tamriel under the banner of the Empire and the Septim Dynasty begins. Since the beginning of the Third Empire of Men, there have been many civil wars and revolts against the Empire's rule. Notable events of the Third Era include the Nerevarine's victory over Dagoth Ur and the Akulakhan, the second eruption of Red Mountain, and the assassination of Uriel Septim VII, which would lead to the Oblivion Crisis. Martin Septim's sacrifice during the Crisis marks the end of both the Septim bloodline and the Third Era.
The Fourth EraEdit
The Fourth Era begins with the end of the Septim bloodline during the events of The Elder Scrolls IV: Oblivion. It marks the rise of the Thalmor and the establishment and rise of the Third Aldmeri Dominion, as well as the Great War with the Third Empire. The last known year of the Fourth Era is 4E 201, the year in which the Dragon Crisis occurred and the Last Dragonborn rose to combat the World Eater, Alduin.