Post-Covenant War conflicts

Following the end of the Human-Covenant War in 2553, the Unified Earth Government and its United Nations Space Command became embroiled in a major conflict with a formidable remnant faction declaring itself as a revival of the original Covenant.

The war was instigated by the Sangheili Jul 'Mdama as revenge for the death of his wife Raia during the Sangheili civil war, blaming humanity for the event due to their involvement. Seeking both a new spiritual voice for their people and a chance for revenge against the victorious UNSC, 'Mdama sought to travel to Requiem to unlock the world's secrets. During his time in captivity on ONIRF Trevelyan, he had learned that the Didact, a mighty Forerunner general with a hatred for humans, was trapped inside and sought to release him in order to achieve vengeance on humanity.

The hostilities began when a Covenant fleet led by Merg Vol invaded the UNSC research colony Draetheus V and its moon, X50, beginning a major battle which prompted the involvement of the UNSC Navy's most formidable warship,, and its SPARTAN-IV contingent. The war continued in 2557, when the Covenant finally gained access to Requiem. The ensuing series of skirmishes led to the Didact's release and an alliance between the Promethean forces and the Covenant, who revered the Forerunner as a "living god". Covenant forces subsequently helped him retrieve the Composer. Although the Didact was later defeated by John-117 in a battle over Earth, the Covenant continued to occupy Requiem, searching for the Librarian. They contested the UNSC for control of the shield world again in early 2558; the drawn-out battle eventually culminated in the installation's destruction but not the defeat of the Covenant, who had already withdrawn most of their forces from Requiem. Additionally, they managed to capture a significant UNSC asset, Dr. Catherine Halsey, who was seemingly willing to collaborate with 'Mdama. Both the UNSC and the Covenant also ended up with a half of the Janus Key.

List of appearances

 * Halo 4
 * Spartan Ops
 * Halo: Spartan Assault