The timeline below offers a brief summary of some of the major events in the Old Republic era.
Note: Dates here used are BTC and ATC, which are Before and After the Treaty of Coruscant as the date epoch. The BBY (Before Battle of Yavin) values are also included here for convenience.
The Great Galactic War
- 28 BTC (3681 BBY) – The Sith Empire returns from deep space and declares war on the Galactic Republic. They begin blocking trade routes and successfully retake Korriban, the Pureblood homeworld. Rattatak is also discovered.
- 15 BTC (3668 BTC) – The Dread Masters are captured.
- 8 BTC (3661 BBY) – The Hydian Way is blockaded, remaining in place for a full year.
- 0 ATC (3653 BBY) – The Sacking of Coruscant. A treaty is signed marking the end of the Great Galactic War.
- 2 ATC (3651 BBY) – Tython is rediscoved by the Jedi.
- 11 ATC (3642 BBY) – The cold war ends, with various conflicts and proxy battles sparking the Second Galactic War.
Second Galactic War
- 12 ATC (3641 BBY) – The Empire discovers the Republic prison planet, Belsavis. The Sith Emperor’s body is killed, leading Darth Malgus to form a splinter faction of the Empire. This faction and Malgus are killed on Ilum by a joint Republic and Empire effort.
- 13 ATC (3640 BBY) – Makeb is hit by violent cataclysms due to Imperial mining operations, while the Republic secures a treaty with the Hutt Cartel and evacuates the population. The planet is destroyed.
- 13 ATC (3640 BBY) – The Dread Masters raid Gree space, before their forces are pushed back by a Republic-Empire alliance.
- 14 ATC (3639 BBY) – The Dread Masters make their final stand on Oricon but are defeated by a Republic-Empire alliance. Meanwhile CZ-198 is assaulted by both Republic and Empire forces to confiscate assets.
- 15 ATC (3638 BBY) – Tython and Korriban are both raided by the Empire and Republic respectively, leaving both bases of operations razed. A genetics laboratory on Manaan was attacked by a strike team, revealing a Revanite conspiracy.
- 16 ATC (3637 BBY) – The Republic and Empire continue their temporary alliance to stop the Revanite crisis on Yavin 4, revealing to both sides that the Sith Emperor is still alive. The spirit of Revan is put to rest and the Order of Revan brought to disarray. Meanwhile, the Emperor consumes all life on Ziost, leaving the planet devoid of the Force while his spirit fled to the far regions of the galaxy.
Rise of Zakuul
Note: Spoilers for Knights of the Fallen Empire and Knights of the Eternal Throne follow.
- 16 ATC (3637 BBY) – Continuing their temporary truce to search for the Emperor deep in space, the Eternal Empire of Zakuul lays waste to the search party. The Emperor, now known as Zakuul’s leader Valkorion, is supposedly killed. Zakuul then proceeds to dominate the known galaxy with ease, through the power of the Eternal Fleet.
- 17 ATC (3636 BBY) Both the Republic and the Empire sign treaties with Zakuul and their new emperor Arcann, ending the Second Galactic War (although some smaller conflicts between the Republic and the Empire continue). Star Fortresses are placed above key planets as a deterrent.
- 21 ATC (3632 BBY) – The Odessen Alliance is formed to take down Zakuul. During that same time, the Crescent Coalition has also amassed a moderately sized power base, aimed at disrupting and destroying the Eternal Empire’s operations on many homeworlds such as Alderaan, Nar Shaddaa and Quesh.
- 22 ATC (3631 BBY) – Fall of the Coalition, leaving the remaining members scattered across the galaxy, with their main bases the Crescent Enclave and flagship the Celestial destroyed. A few months later, the survivors found Aurora Core and are given full operation autonomy by Republic Special Forces and sets up their new command post on Coruscant.