United Earth Confederacy

The United Earth Confederacy (UEC), commonly known as the Confederacy, was a political, economic and military union between all human-inhabited worlds and other colonies. Representing humanity as a whole, its main goal was to prevent any of its citizens from ever seeing another major war (or similar large-scale suffering, like famines, mass poverty, pandemics, etc). It was destroyed in 2792 CE by the Compact of Species.

The Second Diaspora
Once the shift drive was invented in the 2400s and faster-than-light travel was possible, communication and transportation between the independent colonies was now something that could be done without taking years at the very least. Earth brought the colonies together (some more willingly than others; the UECN was formed to bring several in line) to form the United Earth Confederacy. The comparatively rapid rate of expansion following this was known as the Second Diaspora, and ushered in a golden age for humanity.

After the newly formed United Earth Confederacy Navy's role in the unification, it was relegated to mostly anti-piracy duties (what little of it there was) and security. As one of the goals of the UEC was to make sure humanity never fought another war, it received very little funding and was seen by the public as a continuation of the military-industrial complex that had, in part, led to the wars following the plague. It was continually drawn down in size over time, until the war with the Compact proved that this goal, at least, was a naïve one.

First Contact
In 2782 CE, a Confederate explorer ship, the UECSS Alaskan Dawn, encountered the Compact armed explorer CSSS Flickering Light. Initially excited to have contacted another interstellar government, the crew of the Alaskan Dawn slowly realised, to their horror, what kind of place the Compact really was as the crew of the Flickering Light recounted their doctrine towards other species (bringing a harsh reminder of the old "white man's burden" line of thinking from ancient Earth). The crew of the Alaskan Dawn tried to destroy the Compact ship to buy time for the Confederacy to prepare for the inevitable war, but without realising the technology disparity between the two powers (and that the Compact knows there are other, worse horrors that lurk in the dark already, and arms their explorers as such), it lost the fight. The Compact scout returned home with the tale of an advanced, hostile and treacherous nation, and war followed.

The Compact-Confederate War
Main article: The Compact-Confederacy War

Due to massive ideological differences between the Compact and Confederacy, humanity refused to join the Compact of Species. The resulting Compact-Confederacy War lasted from 2782 CE to 2792, ending with the destruction of all human holdings and extermination of all humans the Compact found. One exodus fleet arrived at Rally, colonising it before being discovered by the Compact several hundred years later. Red One and UECNS Nemesis also remained at large following the war, and as the sole known surviving member of any part of the Confederacy's military or civilian command hierarchy, would essentially become its acting President.

Proximal Flame created a few snippets about war:

https://forums.spacebattles.com/threads/the-last-angel.244209/page-132#post-17182885

https://forums.spacebattles.com/threads/the-last-angel-ascension.346640/page-7#post-18265928

''Note: as with many other things in the Angelverse, precise dates/figures/statistics etc have not been provided about the Confederacy. As such, those given here are educated guesses, working backwards from what parts of the timeline we do have.''