After almost a full season's worth of teasers, Agents of S.H.I.E.L.D. has finally revealed the cosmic Confederacy who are threatening the Earth. They were first introduced when S.H.I.E.L.D. stepped into a dystopian future, one where the Earth had shattered like an egg, and the Kree ruled over the last remnant of the human race. At first, it seemed the Confederacy was actually an alliance of Kree ruling houses; little by little, though, we've learned the truth.
It seems the Confederacy is a thousand-year-old alliance between different groups, each representing a race who are brutally militaristic and steal resources from other worlds. While membership has changed a little over the course of the millennium, for the last few hundred years there have been six members of the Confederacy. The latest episode, "The One Who Will Save Us All," revealed all but one of these races.
These alien races all originate from the comics, although some are pretty deep cuts. What's more, many of them could prove to be a terrifying threat to Earth's defenders. Let's take a look at the alien races who are part of the Confederacy.
The Kree were the first members of the Confederacy to be introduced in season 5. It's worth noting, though, that the entire Kree Empire is not part of the Confederacy; rather, only the ancient ancestral House Kasius is. The first half-season implied that the rest of Kree society look on House Kasius with some level of disdain, perhaps even disapproving of the Confederacy. This is a smart way of differentiating S.H.I.E.L.D.'s Kree from the ones introduced in next year's Captain Marvel; any differences between the portrayals are simply the differences between House Kasius and general Kree society.
House Kasius seem to play an important role in the Confederacy, and it's likely they're the group who are particularly interested in Inhumans. The Inhumans were created by the Kree millennia ago to be front-line weapons and servants. Certainly it doesn't seem to be a coincidence that, in the future timeline visited by Coulson, it was House Kasius who took control of Earth and attempted to breed Inhumans.
The Remorath (or "Marauders") don't appear to have a direct comic book parallel. The Remorath enjoy the thrill of the hunt, and generate a bioelectrical field that shorts out electrical circuitry around them. They clearly have advanced senses, and use the darkness as lights go out to their advantage. Qovis is leader of the Remorath, and he seems particularly interested in Earth's Gravitonium deposits. It seems likely that the Remorath are typically a race of space-raiders, who attack cargo vessels or unprotected worlds and take their plunder. If that's the case, presumably the other members of the Confederacy are protected from these intergalactic Marauders as part of the treaties binding the group together.
It's possible Marvel Television named the Remorath after a Star Trek character, Morath, brother of the Klingon's venerated Kahless. If so, it's a reference both to the ferocity of their fighting spirit and to their untrustworthy nature; Morath was best known for dishonoring himself and his family by breaking his word.
The Rajaks are quite a deep cut from the Marvel Comics universe, but this isn't the first time they've been mentioned in the MCU. In Guardians of the Galaxy, Peter Quill made a throwaway reference to sleeping with "a smoking-hot Rajak girl."
Created by Stan Lee and Larry Lieber, the Rajaks were introduced in Tales of Suspense #57, back in 1964. That issue's an important one in Marvel history, as the first story in it introduced Hawkeye - then imagined as a criminal who attacked Tony Stark. The Rajaks appeared in the secondary story, which saw a race of space pirates attack the Watcher's homeworld. They believed the Watcher would be sworn not to interfere, but were wrong; he was allowed to protect his home, and repelled the Rajaks with ease.
Talbot actually absorbs the Rajak leader into himself, which raises the disturbing possibility that he's now being influenced by their culture and ways. Meanwhile, the Rajaks are known to be brutal and vindictive, and are sure to seek retribution for Talbot's act.