500,000 BBY* – Most civilizations have history that we can make heads or tails of Also, the Devaronians invent space travel! So we can have HISTORY IN SPACE HOW COOL IS THAT.
100,000 BBY – Coruscant is pretty well covered in what will eventually be called “Galactic City,” and takes the first steps toward its role in galactic politics. Also, the race known as the Sith develop their culture on Korriban, focusing on magic and tribalism.
36,534 BBY – An unprecedented gathering of philosophers, mystics, scientists, and other assorted smart people in robes gather on Tython, attempting to codify the metaphysical energies that make the universe go. This is the first time that anyone calls these energies “The Force.” The name sticks.
35,000 BBY – The Rakatan Infinite Empire becomes the first interplanetary government worth paying attention to. They unite the galaxy by essentially kicking everyone in their collective junk. This would prove to be the go-to strategy of future galactic imperial models.
30,000 BBY – The Rakatan Infinite Empire hits its peak, which nobody calls a golden age, because they’re pretty much ugly jerks. They construct The Star Forge – using dark side energies as a renewable energy source, IN ADDITION TO A FRACKING SUN, they don’t solve energy crisis so much as build an endless supply of deathbringing ships and war droids. This is where the whole “infinite” part of their empire starts living up to the billing, as the Star Forge could theoretically produce such things in perpetuity.
It also makes everybody go crazy nuts with dark side energies, but that’s the price you pay.
Also, the Sith King Adas unites the tribes of Korriban into one people. Perhaps unsurprisingly, he is also a giant tool.
27,770 BBY – The Rakata arrive on Korriban, and it’s BATTLE OF THE JERKS as King Adas (who is old as dirt by this point) leads his people to resist the invading armies, the first such civilization to do so. He dies in the process, which really, it was about time for.
In a couple years, his people wind up working for the Rakata anyway, which is kind of ironic.
27,500 BBY – Humans show up on Alderann, and start taking over the galaxy by breeding incessantly.
25,783 BBY – Everybody on Tython decides to use the force to fight over ideology, tearing the planet apart, and killing massive numbers of people. The Jedi Order is formed out of this conflict, and it’s cool robes for everyone from this point out!
25,200 BBY – The Rakata all get sick and die from a plague that not only makes you sick, but cuts off one’s connection to the Force. This is almost certainly unrelated to developments in Sith Alchemy, nothing to see here, move along.
~25,000 BBY – Everybody steals hyperdrive tech from the suddenly absent Rakata! The Galactic (Old) Republic is Formed! The Jedi Council swear loyalty to said Republic! Everybody hugs!
24,000 BBY – Mandalore the First crowns himself thus, and the
brutal conquerors who worshiped war as a living deity happy friendly people begin the traditions that persist to this day.
15,000 BBY – The Hutts conquer the planet Evocar and rename it Nal Hutta. Everybody might hug, but it was probably pretty slimy and gross.
6,900 BBY – Yet another civil war among the Jedi lead to a bunch of people being exiled. They wind up on Korriban, which is incredibly advanced in the mystical arts, but relatively undeveloped technologically. With the Sith species aving reverted to a clan-based government, these exiled “Dark Jedi” roll up ons with their lightsabers and replicator tech, and begin a strange marriage of equal parts mutual exploitation, opression, violence, learning, understanding, and interbreeding. The native state of the Sith being a symbiotic link with the dark side of the force sits pretty well with the dark Jedi, and over time, the philosophies of the two groups intermingle as much as their genes.
5,000 BBY – The Great Hyperspace war! It happens when the Sith Empire accidentally rolls up on the republic. Not even kidding – this one wasn’t on purpose. The Republic eventually wins.
0 ABY – The Battle of Yavin, in which some punk kids blow up the Galactic Empire’s Death Star.