History of the Twelve Colonies
From Battlestar Wiki, the free, open content Battlestar Galactica encyclopedia and episode guide
The history of the Twelve Colonies of Kobol stretches back nearly 4,000 years before the destruction of the Colonies, with much of its ancient history being shrouded in mystery and religious lore.
During the service for the dead following the Cylon attack on the Colonies, William Adama states "Life here began out there," reminding the assembly that this was the first line of the Sacred Scrolls, told to them by the Lords of Kobol uncounted centuries ago. Indeed, the humans of the Twelve Colonies originally lived on the planet Kobol, the purported homeworld of the human race (TRS: Miniseries).
Much of what is known about life on Kobol is gleamed from the Sacred Scrolls, which makes those accounts potentially unreliable. Purportedly, the thirteen tribes lived in an idyllic utopia with the Lords of Kobol, residing in at least one city, the City of the Gods. What the Scrolls do not tell is that the original twelve tribes of Kobol created the Thirteenth Tribe, a race of synthetic beings with the ability of organic memory transfer, allowing their bodies to die but their consciousnesses to download into a new body (No Exit).
The Book of Pythia, recorded by the oracle Pythia on Kobol 3,600 years before the destruction of the Colonies, detailed the exile and rebirth of the human race (The Hand of God). It is not known whether or not this book was a true prophecy predicting the destruction of the Twelve Colonies or a recitation of events on Kobol. Regardless, the book was written in the midst of great turmoil on Kobol.
The prophecy alludes to a "blaze" which descended on the thirteen tribes and against which the Lords of Kobol were powerless to intervene (Home, Part I). The Thirteenth Tribe fled Kobol roughly 4,000 years before The Fall, settling on a planet called Earth.
Approximately 2,000 years later, the remaining twelve tribes also left Kobol. According to the Sacred Scrolls, the populace of the tribes were taken in a "Galleon" (a spacecraft). Athena, a Lord of Kobol, threw herself from the Gates of Hera, to her death. The leaders of the tribes were interred with her, and Zeus warned the survivors that any return to Kobol "would exact a price in blood." After a journey through space, the refugees from Kobol founded the Twelve Colonies of Kobol.
SettlementSagittaron had been exploited for centuries (Bastille Day).
Various shifting alliances and attempts at unified government came out of these conflicts, which would later form the bedrock of the Articles of Colonization, but it would still be some time before a practical Colonies-wide government was established .
The Cylon War
Such was the extent to which the Colonies had invested their military power in the Cylons that when they chose to rebel against their masters, the Colonials found themselves well-matched. With their mastery of Colonial technology, the Cylons were able to infiltrate nearly all networked devices. The Colonials were forced to abandon networked computers and wireless devices in favor of more secure and durable technologies, able to withstand both Cylon infiltration and the powerful nuclear weapons used by the warring parties. Twelve battlestars built in the opening years of the war best exemplified these principles, including Galactica (Miniseries). In response to the great threat posed by the Cylons, the Twelve Colonies formed a unified federal Government for the first time, at the beginning of the war (Colonial Day).
At its darkest hour, the Cylon War came very close to wiping out the Colonies. This outcome of the war likely developed, among other practices, the Case Orange contingency government succession protocol as well as the re-buildup of the Colonial Fleet in the Federal Era.
After the Cylon War ended, a long and bloody struggle of approximately 12 years, an armistice was declared, and the Cylons departed for a world of their own. The Colonials established a neutral meeting place, Armistice Station, and made diplomatic overtures for Cylons and Colonials to meet annually. However, these overtures were continually ignored.
After the war, the military went through a Reduction in Force, resulting in the discharge of many of the war's veterans.
While the Cylon War had a lasting effect on the government of the Twelve Colonies, the population as a whole, much of it born after the war, had relegated it to a historical note in textbooks. The now-united government continued to maintain a large standing military, which, forty years after the war, had grown to include 120 battlestars (Miniseries), most apparently more advanced than those of the original battlestar class (Pegasus). This buildup apparently began about twenty years after the war, around the time Saul Tigh and William Adama rejoined the military ("Scattered" and its podcast).
With their military assets now concentrated in a central government under the Articles of Colonization (with Caprica City as the capital), the new government of the Twelve Colonies was able to maintain peace among its members (Water). Now presumably free of the Cylon threat, technologies which could not be used during the war were redeployed throughout the fleet, increasing its effectiveness against more mundane opponents (Miniseries).
This new era of federalism was not without considerable opposition. Dissidents on Sagittaron lead by Tom Zarek took arms against the government (Bastille Day), supplied by arms dealers like Leoben Conoy. Regardless of these localized attempts at insurrection, on the whole the Twelve Colonies faced no major military threats, with the loss of contact with the Cylons. The Colonial Fleet's standing numbers were actually kept disproportionately high relative to their common uses, in fear that one day the Cylons might return. Day-to-day work for the Fleet consisted of handling the small-scale brush fire attempts at rebellion such as on Sagittaron, but these were all light peacekeeping actions rather than actual fighting. Prior to the Cylon attack, none of Galactica's younger-generation crew had ever seen any real combat.
Fall of the Twelve Colonies
The arrogance of the Colonials in re-equipping their military with technologies vulnerable to Cylon interference proved to be their undoing. Forty years after the first Cylon War, Cylon infiltrators subverted Dr. Gaius Baltar's Command Navigation Program, allowing an advanced Cylon armada to destroy the Colonial fleet with impunity.
The attack resulted in the nuclear bombardment and occupation of the Colonies and the enslavement of most of the few isolated survivors in a series of Farms. Altogether, less than one hundred ships (mostly civilian) survived the attack, including only two battlestars - the nearly obsolete Galactica and the Mercury class battlestar Pegasus. The survivors abandoned the Colonies and formed a fleet in search of the thirteenth colony, Earth, where they hope to find refuge. However, Earth turned out to be a nuclear wasteland.
Settlement of the new Earth
Despite the discovery that Earth could not sustain human life, the Colonial fleet soon found another inhabitable planet, which they christened Earth in a symbolic homage to the original planet. They discovered that, despite the impossibly small odds, another group of primitive humans had naturally evolved on the planet.
In a collective decision, the survivors chose to surrender their technology by sending their fleet into the Sun; they then dispersed in groups across the planet. Though some cultural memes of the Colonies survived, such as belief in the Lords of Kobol in the form of the Greco-Roman pantheon, maintaining the history of humanity proved impossible without technology. By the time an advanced society reemerged on the planet nearly 150,000 years after settlement, the knowledge of Kobol and her Twelve Colonies had been lost.