|Date:||1000 between 0 yahren before Destruction of The Twelve Colonies|
|Result:||Decisive Cylon victory, destruction of the Twelve Colonies|
This conflict began when the Colonies aided the Hasari in taking back "their nation" from the Cylons. The exact nature of the Hasari and their relationship to the Colonies remains unknown (TOS: "Saga of a Star World").
Battles of the War
The following were known events during this conflict, in chronological order:
- Battle of Cosmora Archipelago: This is the earliest known conflict, with Commander Kronus and the Fourth Fleet victorious against the Cylons (TOS: "Take the Celestra")
- Battle of Caprica: This occurred during Leda's lifetime (TOS: "The Gun on Ice Planet Zero, Part I")
- Attack on Umbra: A Cylon attack on Caprica, presumably on Caprican agricultural resources, which leaves Starbuck and several hundred children orphaned (TOS: "The Man with Nine Lives")
- Battle of Molecay: This is the last known major battle with the Cylons. The Fifth Fleet, lead by the "legendary Commander Cain", is destroyed here, save Cain's battlestar, Pegasus (TOS: "The Living Legend, Part I")
- Battle of Cimtar: The final coup de grâce, resulting in the fall of the Twelve Colonies (TOS: "Saga of a Star World").
Effects of the War
Given the war's duration, it appears that efforts normally occurring during peacetime were curtailed. Apollo mentions to Zac that they would be able to resume deep space exploration should there be peace with the Cylons (TOS: "Saga of a Star World"). The Rising Star's maitre d' states that the festivities during the departure from their home galaxy remind him of a "time before the war" (TOS: "The Long Patrol"). This might suggest that there were lulls between major battles of reasonable length, or he might very well have been speaking of the time before the exodus from the Colonies.
In addition, the Colonials set up numerous colony worlds far outside their galaxy, which included the prison planet of Proteus (TOS: "The Long Patrol") and agricultural settlements such as Sectar (TOS: "The Magnificent Warriors"). These planets became cut-off from the Twelve Colonies, resulting in a loss of technological advancement, even regression; Proteus, for instance, uses Sixth-millennium starfighters that predates the mainstay seventh millennium Colonial Viper (TOS: "The Long Patrol"), heavily suggesting that the war took its toll on the supply and transportation lines between the main colonies and their smaller intergalactic interests to the point where whole worlds and outposts were forgotten about.
The Thousand-Yahren War ends at the Battle of Cimtar. Lord Baltar, a Colonial double-agent for the Cylons, tricks President Adar into believing the Cylons wished to negotiate a truce. The peace conference is a ruse, allowing a force of one thousand Raiders to destroy four of the five battlestars, including Adar's Atlantia, while a basestar fleet (and additional Raiders) destroy the Twelve Colonies (TOS: "Saga of a Star World").
With Baltar's agent, Karibdis, neutralizing the Colonial defense systems on Caprica, the Cylons are able to attack the planet without planetary resistance (TOS: "Murder on the Rising Star"). Strafing runs and pluton bombs are used to devastating effect by the Cylon assault forces.
As an end result, countless humans are killed and the Colonies are neutralized as a home for the Colonials.
From the ruins of the Colonies, surviving Colonials are gathered into a motley fleet of 220 civilian ships and are escorted to safety by the last surviving battlestar, Galactica (TOS: "Saga of a Star World").
In the separate continuity
In the Berkley novelizations, Adama states in his journal that the conflict began when the Cylons attacked Colonial merchant ships (destroying them by the thousands) and, later on, sent an attack fleet to the Twelve Colonies. This attack was repulsed by a prepared Colonial military, which began the thousand year war.
- See the separate continuity section of this article for differences between the novelization and the actual canon versions.
- On page 16 of Encyclopedia Galactica, a non-canonical publication issued in 1979, gives the number of 70 billion. No exact number is provided in the series.
- The novelization does not use the term "yahren".
- Thurston, Robert (September 1978). Battlestar Galactica. Berkley Books, p. 1-2.
- It should also be noted that there is a contradiction in this story that occurs later on in the book, as noted on the book's guide page.