It is the year 2258, construction of the space station Babylon 5 has recently been completed, Babylon 5 was built in a neutral space sector to enable a free port for traders and meeting place of diplomats in this part of the galaxy. Babylon 5 created a place were problems should be solved by peaceful means with the purpose to avoid war.
About the individual races in the Babylon 5 galaxy, which are known to the Earth Alliance, there is the following information:
Still relatively new on the cosmic stage, the EA has (so the official abbreviation of the Earth Alliance) quickly advanced after first contact with the Centauri Republic where they first got the technical know-how to build jump gates and hyperspace engines enabling the to settle several colonies on other solar systems founded. Before encountering considerable problems with the Mars colony, which strives for independence.
The first contact with the Minbari Federation about ten years ago ended in a fiasco with the destruction of the Minbari ship, which resulted in a bitter war, in which the Earth forces was dominated by the far superior technology of the Minbari. In the final battle ("Battle of the Line") all the spaceships still available were pulled together to form a defensive perimeter around the Earth.
Just as the Minbari fleet was close to victory, the commander of a Starfury squadron called Jeffrey Sinclair ( the new commander of Babylon 5) tried to ram the nearest Minbari cruiser with his damaged fighter . Sinclair lost consciousness, but came 24 hours later regained consciousness and learned that the Minbari had surrendered themselves. No one knew why, but on Earth, the event was hailed as a great victory.
Once a powerful expanding stellar empire, the Republic fell slowly into decadence and gradually lost more and more colonies. The internal intrigue seemed to be much more interesting. Today, the Republic consists only of the main world "Centauri Prime" and about 12 colonies. When the Centauri made contact with the EA the Centauri tried to pretend that the earth was a long forgotten Centauri colony, but the DNA test soon showed this to be false. Today the Centauri dream of past glories and are already known more as an interstellar tourist attraction.
Narn was once a peaceful, technologically backward world, when they were conquered by the Centauri who enslaved its inhabitants. In their hatred of the oppressors of the Narn farmers turned to warriors and began a long battle with the Centauri to win back of their world. The hatred continued to live on and the Narn exploited their world in order to allow the construction of a large arms industry and even to found colonies. In Earth-Minbari War, the Narn supplied arms to EA. The Narn are also are one of the only races to not have any telepaths.
The Minbari Federation is the oldest among the "young" races. Ruled by the "Grey Council" which consists of nine-members of the ruling elite, composed of three representatives of the three castes (workers, warriors, religious). The Minbari have been part of galactic events for over a 1000 years.
No one knows how Vorlons really look as you wear encounter suits, they are a very old race and no alien ship has ever returned from there territory. Their technology is very sophisticated, their ships consist of biological components. Other than these, there are just a lot of rumors about them.
League of Non-Aligned Worlds
The non-alligned worlds is an association of representatives of the independent worlds and little star empires from around the galaxy. Interesting map of the galaxy of Babylon 5, see how the different races are located with each other