- Most of ONI will be purged from the UNSC. Parangosky is a Templar will be assassinated, followed shortly afterwords by Osman and any other would-be successors. I'm hoping for a brutal death by insurgents or even a detachment of Spartans, so then there won't be any backlash against the Sanghieli, who should rightly have the honors.

- 'Mdama and the Covenant remnant are just some rebels who managed to steal some ships, and in no way represent the majority of Sangheilios which has come under some control and civility with the Arbiter at it's head, finally gaining support from it's citizens.

- Spartan IV will be shut down, but Spartan will remain as a UNSC branch and it's personnel (under the new leadership of Fred) will no longer answer to ONI.

- Halsey's "revenge" will be fulfilled when she finds whatever is left of ONI (perhaps an escaped Parangosky/Osman) and directs the Covenant Remnant to exterminate them.

- Halo 4 Jackals are actually the species that Jackals evolved from. Jul couldn't convince any real Kig-Yar to join his cause, so he just recruited some of their trained monkeys, in essence.

Heh, well that covers recent fiction I guess. Here's some other stuff:

- FOA. Always FOA.

- Gamma Company survived the end of the war and the majority of it's personnel were integrated into Spartan-IV. They, along with whatever is left of Blue team, will form their own group of Spartans that get deployed for high-value missions reserved for "real" Spartans.

- The existence of Noble Team and Headhunters (and perhaps other S-III groups like them) justified the large number of Mjolnir variants there were by 2552.

- The Covenant dig in the Yucatan was searching for a Forerunner artifact that had been built on top of and worshiped by the Mayans and other Central American nations. This artifact was in fact there for the purpose of locating a Precursor artifact that had crashed into the Yucatan 65 Million Years ago and eliminated the Dinosaurs so that the Precursors could shape intelligent life out of Mammals.

- The Forerunners maintained a research station in Antarctica, which was abandoned and eventually buried in ice.

- The Assembly is aware of or perhaps even in contact with the Domain.

- The Covenant never fully glassed planets (with the possible exception of Reach), only areas where humans were located. Thus it was possible for some humans to survive a glassing, and also likely that the Covenant would afterwards use the world for their own purposes.

- Truth went mad in Halo 3 because of the loss of High Charity. He had planned for the deaths of Regret and Mercy, but not for the mass extinction of the majority of his race. He lied so much over the years that, at the end, he actually started to believe it.

- Master Chief carries the memories of the IsoDidact, Halsey and Cortana the Librarian, and this is what the Librarian "unlocked" in Halo 4, besides his immunity to the Composer. Also, Cortana was unknowingly copied by the Librarian when she was in the system and will return in Halo 5/6.

- The Gravemind and Cortana moments in Halo 3, along with hearing the Didact's voice in 4 when Cortana couldn't (Shutdown), are a result of Chief's geas. He can hear those with whom he's most linked to, which goes along with the above theory. Cortana because of the Librarian, UrDidact because of the IsoDidact, and Gravemind due to Precursor space magic lol.

I've got more, but I spent like an hour typing this instead of getting stuff done I need to do, so... :p