The Earth Alliance was the largest Terran faction in explored space, and it tended to cultivate good relations with it's neighbors. However, being led mainly by humans, they were incredibly impulsive and often end up in wars they never planned for.
The Earth Alliance government was democratic, with elections every few years. There was no term limit for any position, so it was possible to remain in office for a lifetime if you were particularly well-liked, but that never happened. In contrast to other large democracies in Earth's past, the Earth Alliance had no president, it instead had a single, large council. Elections were held by popular vote, none of the elecotral college that plagued the United States. The economy was socialist, verging on communist, with equality heavily enforced. All corporations were owned and operated by the government, which made sure that all of the workers got a decent wage and proper working conditions. Only small businesses that follow the strict government guidelines were allowed to be independent, large corporations were outlawed and founding one was punishible by exile if you did not turn it over to the government.
There were thousands of religions and beliefs within the Earth Alliance, and it would be a waste of time to even try to list them all. However, there was a single binding concept: The Common Sense Doctrine. This doctrine bound all the Alliance together with the idea of inferiority. Not the inferiority of other species, but the inferiority of humanity itself. Strangely enough, this doctine came after the most horrific war known to humanity: The Common Sense War. Over three hundred billion people died in it, along with entire planets. Usually when a species goes through such a thing, they realize that the universe is a harsh place and bind together to destroy or enslave other species under a doctrine that declares them superior. The exact wording of the doctrine varies, but the one that places humanity higest states that it is inferior to all sentient beings, the one that places humanity lowest states that they are the lowest form of life in the entire multiverse.
After the 3rd World war in 2031, the remaining nations of the earth bound together to form the EA (earth alliance). In 2057, at a secret EA facility in Antarctica, the EASS Galileo was launched. The first ship to use the new negative energy warp drive, the Galileo was able to reach star systems up to 200 light-years away from earth within a few short years. This ushered in a new era of space travel, the EA began producing large numbers of starships and by 2123 they controlled every star system withing 200 light-years of earth. The EA had debated moving out further, but every time someone put the notion forward it was rejected, as most of the citizens were afraid of contact with hostile aliens. Finally, in 2133, they were able to get the idea through the paranoia of the citizens, the vote was on the side of expansion, with just enough people voting for it for it to pass. The EA began construction of a faster FTL and by 2137 they were able to reach out further and faster. The EAS Hawking was launched with this new FTL. During the Draconian War, the EA was a major player. They are credited with getting the nations of the Milky Way to ally and build up their military through multiple unorthodox ways, one of which was acting threatening so that the other nations would prepare for war. As they despised the Draconians the most (before the attack on the Aetherii), they now have an insanely large military. However, during the war Earth was destroyed by the Draconians. While this had little actual impact due to most of it's surface already being scorched, it was a great blow to the morale of the EA. Recently, the Earth Alliance was broken apart by a second Common Sense War dubbed the Doctrinal Conflict, resulting in an even harsher version of the Common Sense Doctrine. It was dissilved and reforming into the Allied Insterstellar Federation .