History of the Covenant

The Covenant divide their history into periods called Ages. There are at least eight ages, although their exact order is uncertain. The Ages are named according to things that have happened/are happening in them. This also means that the lengths of the Ages vary, with some longer than other. One of the problems with ordering the Ages is that there may be several ages with the same name. At the start of Halo 2, subtitles gave the date as the 9th Age of Reclamation. This suggests that eight other ages of Reclamation have gone before it. The standard version of Covenant history in the article The Covenant does not appear to take account of this.

The Ages
Little is known about their history except that the Prophets and Elites' ancestors waged war on each other, but they formed the Covenant after finding evidence of the Forerunners and their "Great Journey".

One of the leading theories is that the Age of Abandonment was the time when the Forerunners left the Prophets and Elites to embark on the Great Journey.

Elites and the Prophets began fighting each other in the Age of Conflict. It is not yet known why this war started.

In the Age of Discovery, the Prophets discovered the remains of the Forerunner technology, maybe with the help of the Engineers.

During the 1st Age of Reconciliation, the Prophets shared the information learned about the Forerunners with the Elites. The Elites and the Prophets made a truce to unite to form the Covenant with the Elites being promised salvation in exchange for their services as the military and protection. Presumably, this is when the Covenant Writ of Union was created.

The Age of Conversion was when the Elites and the Prophets started to conscript other races (such as when they "tamed" Hunters) into the Covenant through religious conversion or force.

The Covenant began to doubt the word of the Prophets during the Age(s) of Doubt, due to the fruitlessness of their search for Halo. The Grunt Rebellion probably occurred during this span of time.

During the Age(s) of Conversion, the Covenant integrated other races into their organization.

Halo 1 and Halo 2 take place during the 9th Age of Reclamation. It is often speculated that this is a reference to the name that the Monitors give to humans: "Reclaimers". Others, especially the Elites, wonder why the humans, a worthy opponent that have proven themselves in battle many times, were not given the opportunity to join the Covenant. Some within the Covenant even wonder what the humans have done to be an "affront" to the gods. This fact might be linked with humans presumably being the reclaimers.