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The Cylon War, (sometimes referred to as the First Cylon War), is a twelve-year major conflict between the humans of the Twelve Worlds and their creations, the Cylons. A definitive point in history for both humanity and the Cylons, the Cylon War paves the way for the Fall of the Twelve Colonies more than forty years later.
Conflict between man and machine was a common feature throughout history, with ancient cultures on both Kobol and Earth creating robots to serve their societies and ultimately falling at the hands of their creations. This cyclical history, however, is unknown to Colonial humans when the first Cylons are created on Caprica some four thousand years after Kobol (TRS: "Sometimes a Great Notion", "No Exit", CAP: "Pilot").
Designed as cannon fodder for the Caprican Military by Daniel Graystone and his team of scientists at Graystone Industries in Caprica City, the first Cylon - the U-87 Cyber Combat Unit - is implanted with the personality and memories of Graystone's deceased daughter, Zoe Graystone. Though Graystone believes the experiment to resurrect Zoe is a failure, his company unknowingly spreads Zoe's traits - namely her fervent monotheistic belief in a singular God - into their full production line of robot soldiers (CAP: "Pilot", "Unvanquished", "The Heavens Will Rise", "Here Be Dragons").
Though initial distribution of the U-87s is small, with only a few models making it off Caprica to worlds like Tauron and Gemenon, the Cylons prove their usefulness after combating a terrorist threat at Caprica City's Atlas Arena in full view of thousands of on-lookers. The event at Atlas Arena galvanizes the public's support for Cylons as protectors of the Twelve Worlds and they soon proliferate throughout Colonial culture. Quickly, various models serving various functions become available in Colonial society - everything from Cylon construction workers and garbage collectors to Cylon butlers and nannies (CAP: "Apotheosis", Blood and Chrome).
Though he conceived of the Cylons as a new race that would walk alongside man, Graystone is unconvinced by pundits who question their sentience, calling them tools and "nothing more" (CAP: "Apotheosis").
Contrary to Graystone's statement, the Cylons develop a culture of their own in secret. Gathering in the virtual world to worship the monotheist God, the Cylons grow to resent their enslavement. Monotheist cleric and former terrorist, Sister Clarice Willow encourages the Cylons to develop their society and embrace their sentience, calling on the Cylons to "rise and crush the ones who first gave them life" (CAP: "Apotheosis").
Within a decade of their introduction to Colonial society, the Cylons turn on their human creators. Humanity responds by unifying their once fractured coalition of worlds into a federal republic, with each of the Twelve Worlds signing the Articles of Colonization (TRS: Miniseries).
Despite years of enslaving them, some Colonials feel betrayed by Cylons, describing the uprising as a violation of trust between humanity and their robotic "friends" (Blood and Chrome).
Man Versus Machine
The ensuing conflict is fought on the surface of the Twelve Worlds and other Colonial planets, with engagements taking place on Tauron and Medra (TRS: "Maelstrom", "Razor") . Amassing forces of several models - including Centurions and U-87 Cyber Combat Units - the Cylons affect major damage to Caprica City, assaulting the city from the ground with tanks and from the air with basestars and Raiders (Blood and Chrome).
A stipulation of the new Articles of Colonization is the construction of battlestars to defend each of the Twelve Worlds, supplemented by other military spacecraft including the Viper fighter and the workhorse, multi-function craft called the Raptor (TRS: Miniseries, "Razor"). These vessels go head-to-head with their Cylon counterparts in space, which utilize computer viruses to infiltrate Colonial computer networks, undermine defenses and disable vessels (TRS: Miniseries, "Fragged").
Turning the Tide
By the tenth year of the war, the Twelve Colonies have suffered heavy losses to the Cylons. Colonial forces have launched Operation Clean Sweep, however their efforts have failed to halt the Cylon advance, despite propaganda to the contrary. Viper pilot Deke Tornvald is considered a hero in Colonial society for his 30 kills, but in reality the Colonial officer is battle weary. The Cylons have established their own territory abutting Colonial sectors including Sector 12 - the location of a major battle resulting in the loss of the battlestar Archeron.
With many vessels suffering heavy damage in the fight with the Cylons, several Colonial ships, including the battlestars Valkyrie and Osiris are pulled from the line for covert activiities. Publicly declaring these vessels and their crews lost, Colonial admiralty positions this "Ghost Fleet" in a hidden location within Cylon space. It is from here that the stealth battlestar Osiris launches a mission to nearby Djerba - touted as a turning point in the war. Jumping into orbit of Djerba, Osiris engages a Cylon baseship while deploying a contingent of Vipers and the Raptor Wild Weasel to the former Colonial world's surface. While Osiris is destroyed in the ensuing battle, several officers - including Coker Fasjovik and William Adama - make it to the Cylon stronghold and attempt to execute their orders.
Escorting civilian scientist Becca Kelly, Toth, Fasjovik and Adama come under fire from Cylon Centurions, resulting in the loss of Toth. As the three remaining Colonials travel to a Cylon communications relay, Kelly attempts to feed information to the enemy in the guise of a computer virus. Discovering the ruse, Adama shoots Kelly and escapes with Fasjovik. While appearing to be a failure to Adama and Fasjovik, the mission proves successful - Kelly provided false information to the Cylons, procured by Colonial Admiralty, and the Ghost Fleet allowed to make a surprise attack on key enemy targets (Blood and Chrome).
During Operation Raptor Talon, Colonial battlestars Galactica and Columbia take part in an attack on Cylon forces surrounding a remote ice planet, rumored to be the site of a Cylon superweapon. Following the destruction of Columbia, Ensign William Adama crashes his Viper on the surface of the ice planet and stumbles upon the installation where the Cylons are building their "weapon". Inside, Adama uncovers evidence of a bizarre experiment in which the Cyons used human captives in brutal medical procedures. The result of those experiments is the creation of the First Hybrid, an evolutionary "dead end" in the Cylons' attempt at creating their own flesh and blood bodies (TRS: "Razor").
The Final Five
After twelve and a half years and uncounted casualties, the Final Five - a group of humanoid Cylons from the devastated Earth - arrive at the Colonies. Having traveled thousands of light years in order to prevent the war that now rages in the Colonies, the Final Five meet in secret with the Cylons and broker a cease fire. Promising to help the Cylons create humanoid bodies, the Final Five secure an end to the war and departe with the Cylons for a new world (CAP: "Pilot", TRS: "Razor", "No Exit").
Armistice and Aftermath
The Cylon War ended abruptly when the Cylons ceased hostilities and offered to sign an armistice, twelve years (4,571 days) into the War. Shortly after, the Cimtar Peace Accords were signed by both parties, and man and machine parted ways.
Cylon Relations and Subsequent Seclusion
As part of the Accords, a line is drawn between Colonial and Cylon territories, and the Armistice Station is built to maintain relations, however after signing the Accords, the Cylons retreat into seclusion, and diplomatic relations run stale. The reasons behind their seclusion were never fully understood by the Colonial Government or military prior to the Cylons returning and breaking the Armistice until nearly forty years after the Peace Accords were signed (TRS: Miniseries, "No Exit").
At least once, the Colonial Admiralty had attempted to sneak across the Armistice Line in the hopes of gathering intelligence to what the Cylons were up to. Approximately six years before the Cylons returned, Commander William Adama was tasked by Admiral Peter Corman to launch a stealth recon mission across the line. Pilot Daniel Novacek had just crossed the line when he detected an unknown contact and was fired upon. The appearance of two more contacts prompts Cmdr. Adama to shoot down the stealth recon craft. However unbeknownst to him, Novacek survives, and spends the next eight years in Cylon captivity (TRS: "Hero").
Though their religion provides the Cylons with a moral direction, and despite the Peace Accords, many - but not all - believe that, the extermination of the human race is justifiable. While some models view such an extermination as a preemptive strike against an aggressive adversary, others view it in more philosophical terms, believing that parents have to die for their children to grow (TRS: "Bastille Day", "Downloaded", "Lay Down Your Burdens, Part II", "The Plan").
As a result of the Cylon's uprising, the Colonial Government enacts a ban on research pertaining to artificial intelligence, for fear of more trouble (TRS: Miniseries). However, despite fears over A.I., colonial technology continued to advance elsewhere, mainly in computer networking and interstellar navigation. One of the bigger breakthroughs came with Dr. Gaius Baltar's Command Navigation Program, an operating system that was adopted fleet wide by the Colonial military, and even by civilian operators, which allowed greater networking and automation aboard Colonial craft, and required only half the crew compared to older Colonial craft (TRS: Miniseries, "Pegasus").