This is a list of events that occurred in the 2270s. Unless otherwise noted, the timing and sequence of events are taken from "The Babylon 5 Historical Database", published in Across Time and Space: The Chronologies of Babylon 5
With the quarantine on Earth lifted, Stephen Franklin travels to Babylon 5 and purchases a small explorer vessel, intending to explore worlds on the Rim. G'Kar, visiting the station, learns of his plans and joins him on his voyage of exploration and discovery.
Simon Burke, a security officer stationed on Babylon 5, is possessed by Asmodeus while on a vacation to Earth. Father Cassidy and Colonel Elizabeth Lochley figure out how to safely free Burke from this control.
ISA President John Sheridan travels to Babylon 5 in the company of Prince-Regent Dius Vintari, third in line to the throne of the Centauri Republic. After giving a rare interview with ISN, Sheridan is contacted by Galen, given a mission to kill Vintari and make it look like an accident. At the last moment before Galen's plan comes to fruition, Sheridan saves the young Centauri without his knowledge, later inviting him to stay with his family on Minbar.
- Saturday, December 30, 2271
- The Centauri Republic attacks a number of defenseless but strategically valuable border worlds at the edge of their territory, as part of a campaign of increased belligerence towards the Interstellar Alliance. Among the targets are Mipas, Shandukan, Bricarn 9, and Harper's World.
- G'Kar covertly visits Centauri Prime disguised in a Changeling net, when he prevents an assassination attempt on Prime Minister Durla by Lord Yson at a public engagement. To prevent G'Kar from being executed as an offworld spy, Emperor Londo Mollari invites him to stay in the royal palace as his guest, a reward for saving his prime minister's life.
Circa 2276 Edit
- Thursday, December 18, 2278
- John Sheridan and Delenn are captured on Centauri Prime in their attempt to free their son, David Sheridan II.
- Wednesday, December 24, 2278
- After they are released, Delenn warns Sheridan not to go to Z'ha'dum, while he is in a time flux related to events that took place on Babylon 4 many years earlier.
- Emperor Londo Mollari dictates his auto-biography to Vir Cotto, which would later be adapted into The Chronicles Of Londo Mollari and afterward the basis of the ISN docu-drama Babylon 5. Shortly thereafter, he dies along his with long time friend, G'Kar. 
- Vir Cotto rises to the throne of the Centauri Republic after Emperor Mollari dies. He flees Centauri Prime along with Senna Refa and with those heads of noble houses that were able to escape, setting up a government-in-exile on Minbar.
- Sunday, January 4, 2279
- Thursday, January 8, 2279
- Michael Garibaldi and Vir return to Centauri Prime to kill the Drakh leader, Shiv'kala, both to free the Centauri as well as save the life of David Sheridan II.
- When Shiv'kala dies, David is freed from the keeper that was placed on him.
- John Sheridan makes up for lost time by taking his son and Michael Garibaldi on a long-term vacation around the Alliance.
- Friday, January 16, 2279
- Delenn is unanimously elected to the office of president of the Interstellar Alliance.
- After declining re-election to the Interstellar Alliance presidency, John Sheridan becomes the new Anla'Shok Na/Entil'Zha, leader of the Rangers.
- ↑ The Lost Tales mini-comic
- ↑ Final Reckoning - The Fate of Bester
- ↑ Armies of Light and Dark. The attacks on Morbis and Nefua took place in January according to Emperor Londo Mollari II's journal entry, and Durla said they took place six months earlier.
- ↑ Voices in the Dark - Over Here
- ↑ Voices in the Dark - Over There
- ↑ Babylon 5: The Lost Tales
- ↑ Out of the Darkness
- ↑ Out of the Darkness
- ↑ 9.0 9.1 9.2 Sleeping in Light
- ↑ War Without End, Part II
- ↑ 11.0 11.1 Out of the Darkness
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