A timeline of all major events in the Halo universe from the time of the Forerunners through the rule of the Created.
The Great Schism was a conflict between the forces loyal to the Covenant, led mostly by the Jiralhanae, and the Sangheili, beginning on November 3rd, 2552 and continuing off and on until the Rule of the Created in 2558.
At the start of the Covenant in 851 BCE, a group of Sangheili who did not agree with the peace being formed with the San'Shyuum, formed around their leader Ussa 'Xellus and escaped to a previously unknown Forerunner construct known as Shield World 0673.
The Blooding Years is the Sangheili term for the civil war that raged for five years on Sanghelios and throughout Sangheili-occupied territories following the end of the Human-Covenant War and disappearance of the San’Shyuum.
The Siege at Kolaar was an attack on Arbiter Thel 'Vadam and his forces by Avu Med 'Telcam and the Servants of the Abiding Truth in the first major conflict of the Sangheili civil war.
The Attack on Rahnelo was an unprovoked attack by the San'Shyuum Prelate Tem'Bhetek, directed by the former Covenant Minister of Preparation Boru'a'Neem, on the Sangheili colony world of Rahnelo towards the end of 2553.
The Ambush at Duraan was the second part of the prelate Tem'Bhetek's plan to lure in the Shadow of Intent, capture the ship, and kill Rtas 'Vadum.
The Battle of the Prototype Halo Installation was a conflict between Tem'Bhetek, the former Covenant Minister of Preparation Boru'a'Neem, and the Shadow of Intent crew including Rtas 'Vadum and Tul 'Juran.
The Battle of Nuusra was a battle between the remnants of Jul 'Mdama's Covenant forces, the Swords of Sanghelios, and Spartan-IV Fireteam Osiris in the sate of Nuusra on the continent Qivro on the Sangheili homeworld of Sanghelios on October 27th, 2558.
The Battle of Sunaion was a battle between the Swords of Sanghelios led by Thel 'Vadam, their allies Fireteam Osiris led by Jameson Locke, the last of Jul 'Mdama's Covenant forces, and the Created forces led by the Warden Eternal in the state of Sunaion on the Sangheili homeworld of Sanghelios.
938 BCE - 852 BCE
The War of Beginnings was an eighty-six year conflict between the San’Shyuum Reformists who escaped Janjur Qom after the War of Wills and the Sangheili species between 938 and 852 BCE.
860 BCE
The Skirmish of the Planet of Blue and Red was a conflict between the San’Shyuum and Sangheili during the War of Beginnings in 860 BCE.
852 BCE
The Writ of Union was a declaration of peace between the San’Shyuum and the Sangheili, as well as the formation of the Covenant, signed by both species in 852 BCE.
852 BCE - 791 BCE
The Writ of Union not only formed an alliance between the Sangheili and the San’Shyuum, but also commissioned the construction of a great holy city of the Covenant, known as High Charity.
850 BCE
The Rending was a planned disassembly of Shield World 0673, also known as the Refuge, by a group rebelling against the formation of the Covenant in 850 BCE.
789 BCE - 784 BCE
The Taming of the Lekgolo was a five-year campaign by the Covenant to first destroy, and later incorporate the Lekgolo into the Covenant hierarchy from 789 to 784 BCE.
