From Halopedia, the Halo wiki
2535 was a year in the 2530s in the 26th century. It was a turning point in the Human-Covenant War. With the destruction of Jericho VII, most major Outer Colonies had been destroyed. In order to protect Earth and the remaining colonies, the Cole Protocol was established by military order. Human ships must, when forced to withdraw, not move on to a colony-bound vector, even if that means jumping without proper navigational calculations. If blind jumps are not possible, the ship's commanding officer must order a self-destruction sequence if capture is imminent. In addition, it is also imperative that the shipboard AI construct's data core not fall into Covenant hands; thus, part of this protocol involves either the removal or destruction of the ship's AI in extreme situations. Additionally, no captured Covenant ships or technology may be brought back to a human planet without being checked extensively for surveillance devices.
- Jericho VII is glassed by the Covenant. John-117 and the other SPARTANs escape aboard the UNSC Resolute.
- Janissary James is born around this time.
- The MJOLNIR Powered Assault Armor/AA variant is introduced. The helmet is eventually adopted by the UNSC Army's airborne units.
- Lieutenant Jacob Keyes visits Chi Rho and is assigned to the stealth frigate UNSC Midsummer Night.
- Zealot Thel 'Vadamee is appointed Shipmaster of the Retribution's Thunder and elected Kaidon of Vadam.
- Battle of Charybdis IX - Charybdis IX is glassed.
- Battle of the Rubble and the Battle of Metisette - The asteroid habitat known as the Rubble is used to destroy the Kig-yar settlement, the Redoubt, on the surface of Metisette. Most of the Rubble's inhabitants escape on the Exodus asteroid, and head to the 18 Scorpii system. Admiral Preston Cole skip-promotes Jacob Keyes to commander for his actions in the battles.
- The Fleet of Particular Justice is formed following a restructuring of the Covenant Navy. Thel 'Vadamee is made Shipmaster of a cruiser in the new fleet.
- The Assembly, acknowledging the technological inferiority of the humans to the Covenant, discusses fully exposing themselves to their creators and becoming active participants in the war.