I've done my damnedest to reconstruct the history
of Dublin from Ulysses of humans, human-looking robots, robot-looking robots and Cylons on Battlestar Galactica. The dates are purposely vague: I'm more interested in the order in which events occurred than precisely dating them.
5,000ish years ago: Humans inhabit Earth. They leave. Stop at the Algae Planet and build the Temple of Athena so future people can find their way back. Keep on moving and settle on Kobol.
4,000ish years ago: The residents of Kobol create a race of robot slaves that look exactly like humans, i.e. in their own image. These robots can resurrect but not reproduce. Some sort of Blade Runner-scenario maybe ensues? Can't tell but could be important. Either way, the monotheistic Thirteenth Tribe of human-looking robots leaves Kobol and—in Ellen Tigh's words—backtracks to Earth. They stop on the Algae Planet to find the way to Earth. They re-colonize it.
3,500ish years ago: But they are lazy. So the human-looking robots on Earth build robot slaves who look like proper robots. No chance of a Blade Runner-scenario there. Their slaves look like robots. By this point the human-looking robots have acquired the ability to reproduce sexually and do so for so long they eventually forget how to resurrect.
2,000ish years ago (on Earth): The human-looking robots we know as Ellen and Saul Tigh, Galen Tyrol, Samuel Anders and Tory Foster (henceforth "Ellen and the Gang") are born and become scientists. They are warned that their robot slaves plan to destroy them. They rediscover resurrection technology and put a resurrection ship in orbit. The human-looking robots and their robot-looking slaves mutually assure their own destruction—except for Ellen and the Gang, whose brains are downloaded up to their new bodies on the resurrection ship.
2,000ish years ago (on Kobol): Something happens. The Twelve Tribes of humans leave Kobol and settle on twelve loosely-affiliated planets. Each of the Twelve Colonies develops an individual mono-planetary culture because that is what happens in science fiction.
Between 2,000ish years ago and 53 years ago (in Twelve Colonies): Mono-planetary cultures notwithstanding, humans become lazy again. Like the human-looking robots of the Thirteenth Tribe, these humans learned from their mistakes and did not make their new robot slaves in their image. They made Toasters. The Toasters rebelled. The Twelve Colonies unite under the Articles of Colonization.
Between 2,000ish years ago and 53 years ago (on their way from Earth to the Twelve Colonies): Ellen and the Gang move at sub-light speed. Time dialates.
Approximately 53 to 40 years ago: The Toasters and the Twelve Colonies fight a war. On the Toasters' home planet—wherever that is—they try and develop their own human-looking robots. These are the hybrids who control their ships. Ellen and the Gang finally reach the Twelve Colonies. They convince the Toasters to end the war with the humans by promising to help them create human-looking robots.
Between 40 years ago and the Miniseries: Ellen and the Gang are true to their word. The first one they create is named Number One. He's modeled after Ellen's father. He helps Ellen and the Gang create Numbers Two through Eight. He develops issues. Doesn't like that he was created with human limitations. Wants to see nebulae explode in infrared. He orchestrates two plots: one is to kill and have Ellen and the Gang resurrected in the colonies—he wants them to suffer the limitations they imposed on him—and another to have Number Seven, a.k.a. Daniel, permanently boxed. Ellen and the Gang live among the Twelve Colonies until the Cylons attack again by nuking them in the Miniseries and then the show started.
Important Final Point:
One thing that confuses people is that all the robots are called Cylons. They shouldn't be. We should only speak of Cylons when referring to the Toasters, the hybrids they created, and the human-looking robots they created with the help of Ellen, Saul, Galen, Anders and Tory. Why? Because we know that human historians did not refer to the Thirteenth Tribe as Cylons, and the Ellen, Saul, Galen, Anders and Tory are descendents of the Thirteenth Tribe. You could make a larger argument about lineage and descent—the fact that Saul can procreate with Number Six means they belong to the same species—but I'm not about to label as "American" everyone who lives in Russia just because I could father a child by a Russian woman.
Unimportant Brief Note:
In an interview, the biggest name attached to the spin-off, Eric Stoltz, said he was playing a character named "Daniel Graystone" on Caprica. Make of it what you will. Given the timeline sketched above, I think we probably have Number One exiling a Daniel along with Ellen and the Gang because he was Ellen's favorite. Whether this has anything to do with Starbuck—Daniel was supposedly artistically inclined, Starbuck's father was a composer—I don't know.