Tanács előtti időszak (37,000,000 BCE - 500 BCE)
37,000,000 BCE
Egy ismeretlen űrutazó faj elsüt egy részecskegyorsítót egy Kaszás körül, a Mnemosyne bolygó közelében. Ez áthatol a Kaszáson, és folytatja útját az űrön keresztül,végül lecsap a Klendagon bolygón és egy földrajzi érdekességet, a Great Rift Valley-t létrehozva.
298,000 BCE
Az ősi arthenn faj virágzik a Zelene rendszerben, a Helyme bolygón élve,míg egy ismeretlen eset minden élőlény eltöröl a bolygó felszínéről. They also maintained a presence on Epho, another planet in the system, which bears the scars of an ancient orbital bombardment, and on Gaelon, which may have been mined for helium-3.
125,000 BCE
Ancient spacefaring races called the thoi'han and inusannon fight over the planet Eingana, littering the planet with the debris of hundreds of starships. Refined element zero scattered by broken drive cores contaminates the environment, causing many native species to go extinct and those that survive to show a tendency to develop biotic powers.
48,000 BCE: Fall of the Protheans Prothean civilization
The Protheans, a galaxy-wide civilization linked by the mass relay network, mysteriously vanish, leaving only ruins and artifacts behind. Archaeologists will later believe that they were destroyed in a cataclysm.
1900 BCE
Tuchanka, the krogan homeworld, enters the nuclear age. In a global conflict, weapons of mass destruction are released, triggering a nuclear winter. In the resulting devastation, krogan society devolves into a collection of warring clans.
1800 BCE
A supernova propels the Mu Relay, the only point of access to the remote Pangaea Expanse, out of position. Concealed somewhere in the dense nebula formed by the supernova, the relay's position is effectively lost for centuries. Later, the rachni rediscover the relay.
580 BCE
After developing faster-than-light spacefaring capabilities based upon Prothean technology, the asari begin to explore the mass relay network, and eventually discover the huge Citadel space station at a hub of many mass relays.
520 BCE
The salarians discover the Citadel and open diplomatic relations with the asari.
Council Era - Formation (500 BCE - 1 CE)
500 BCE: Founding of the Citadel Council The Citadel
The Citadel Council is formed. The asari and salarians together colonize the Citadel and establish it as a center of the galactic community, led by the Council. This year is also known as 0 GS, the beginning of the Galactic Standard (GS) timeline.
As a gesture of openness with their new asari allies, the Salarian Union opens the records of the League of One. Under threat, the League responds by assassinating the whole inner cabinet of the Union; Special Tasks Group operatives then wipe out the League.
The turian Unification War begins.
First contact is made with the volus although at first they are not permitted a permanent embassy on the Citadel. With their participation, a single galactic currency known as the credit is eventually established, linking all galactic economies.
300 BCE
The Council agrees to grant the volus the honor of being the first species with an embassy at the Citadel, but not a Council seat.
200 BCE - 1 CE
The batarians post an embassy, a century or more after first contact.
The asari stumble into the elcor home system, and help the elcor locate and activate their nearest mass relay. "Within one elcor lifetime" they establish a regular trade route to the Citadel and soon post an embassy.
First contact is made with the hanar and the quarians. The quarians later post an embassy.