Gaius Baltar
the scientist who doomed the Colonies
Dr. Gaius Baltar was a celebrated computer scientist whose vanity and manipulation by a Cylon agent handed the enemy the keys to the Colonial defenses, enabling the near-extermination of humanity. He survived to become Vice President, President, prophet, and finally a reluctant penitent.
Dr. Gaius Baltar was an accomplished computer scientist of Aerilon descent whose ambition and political connections made him a celebrity advocate for re-introducing software networking to military vessels after the Cylon War. Manipulated by the Cylon agent later known as Caprica Six, he gave her access to the defense software she used to cripple the Colonial Fleet, allowing the Cylons to kill billions in mere hours. Escaping among the survivors aboard Galactica's convoy, he spent the years that followed guided and tormented by a vision of Six visible to him alone, drawn through science, politics, and religion toward an unlikely redemption. (Battlestar Galactica, miniseries; Battlestar Galactica, "Daybreak, Part II")
Origins and the destruction of the Colonies#
Baltar claimed to be from the colony of Aerilon, and at the age of ten trained himself out of the Aerilonian dialect into the Caprican one, hoping to be taken for a citizen of a wealthier world. He was the son of a farmer, a background he kept hidden as he rose to scientific celebrity in the years before the Fall. (Battlestar Galactica, miniseries; Battlestar Galactica, "Dirty Hands")
He became involved with a beautiful woman he believed worked for a defense contractor, and to deepen the relationship he gave her access to the highly classified Colonial defense mainframe, an act of treason. In return she helped design a navigation program for Colonial warships, covertly seeding it with backdoors. When the Cylons attacked, they used those backdoors to disable fighter squadrons and sabotage capital ships outright. The woman revealed herself as the Cylon model Number Six, later known as Caprica Six, who had used his access to bring down the Colonies' defenses. She shielded him with her own body from the blast that destroyed his home. Karl "Helo" Agathon then gave up his place on a Raptor for the famed scientist, and Baltar reached Galactica, where he set about ingratiating himself with President Laura Roslin and concealing his role in the genocide. (Battlestar Galactica, miniseries)
Scientist for the Fleet#
Aboard Galactica, Baltar was haunted by visions of Six, with whom he conversed constantly, never certain whether she was an implant, a manifestation of his own mind, or something else. The vision manipulated him through his fear of exposure while granting him knowledge he could not otherwise possess. To deflect suspicion when he realized a Cylon device had been planted in the Combat Information Center, he framed a civilian named Aaron Doral, and soon afterwards he was given the job of building a blood-based Cylon detector. Falsely accused of treason on the basis of fabricated photographic evidence, he was cleared when the photograph was shown to be a fake, leaving his standing stronger than ever. Another threat came in the episode "33", when a defence researcher aboard the Olympic Carrier claimed to know how the Colonies' defences had been breached. (Battlestar Galactica, miniseries; Battlestar Galactica, "33"; Battlestar Galactica, "Water"; Battlestar Galactica, "Six Degrees of Separation")
His apparent gifts deepened his sense of being chosen. Asked to guess the target of a bomb run against a Cylon mining base, he pointed at random and was correct, and came to believe God had guided his hand. (Battlestar Galactica, "The Hand of God")
Vice Presidency and Presidency#
As Caprica's delegate to the Quorum of Twelve, Baltar was elected Vice President with Roslin's backing. He then ran against her for the presidency, far behind in the polls until the accidental discovery of a habitable planet let him promise immediate settlement; the issue swung the election and he was sworn in. During the inauguration, a nuclear warhead he had earlier handed to the Cylon prisoner Gina Inviere destroyed the luxury liner Cloud Nine. (Battlestar Galactica, "Colonial Day"; Battlestar Galactica, "Epiphanies"; Battlestar Galactica, "Lay Down Your Burdens, Part II")
A year of settlement on New Caprica brought hardship, and when a Cylon fleet arrived in orbit Baltar accepted their delegation's terms and surrendered. He learned the Cylons had detected the colony from the light of that same nuclear blast a year before. He remained President only as a figurehead, forced at gunpoint to sign execution orders, though he repeatedly urged the Cylons that their occupation could not succeed. (Battlestar Galactica, "Lay Down Your Burdens, Part II"; Battlestar Galactica, "Precipice")
Trial and redemption#
During the Exodus, Baltar and Caprica Six found the hybrid child Hera, and when the Cylons fled New Caprica he left with them aboard their fleet, where he lived for a time and grew close to the Number Three model D'Anna in her search for the identities of the Final Five. Knocked out by Galen Tyrol in the Temple of Five, he was returned to Galactica in a body bag and imprisoned. D'Anna, Caprica Six and the other Cylons he lived among are profiled in our rundown of Battlestar Galactica characters. (Battlestar Galactica, "Exodus, Part II"; Battlestar Galactica, "Torn"; Battlestar Galactica, "Rapture")
Subjected to interrogation, Baltar admitted his unwitting complicity in the original attack. His smuggled memoir, recasting the Fleet as a class society, made him popular among its working ranks even as it sowed unrest. At his trial, with Lee Adama on his defense team arguing that the Fleet had forgiven many out of necessity, he was acquitted by a vote of three to two, William Adama among those voting in his favor, to Roslin's disgust. (Battlestar Galactica, "Taking a Break from All Your Worries"; Battlestar Galactica, "Dirty Hands"; Battlestar Galactica, "Crossroads, Part II")
After his acquittal Baltar became the reluctant prophet of a largely female following that had built a shrine to him, preaching, under his vision's direction, that God loves all people regardless of their sins. During the assault on the Cylon Resurrection Hub he was gravely injured and, delirious, confessed to Roslin that he was to blame for the attacks; she let him bleed until her conscience moved her to save him. (Battlestar Galactica, "Escape Velocity"; Battlestar Galactica, "The Hub")
The final battle and after#
When Gaeta and Zarek mutinied, Baltar lent Roslin his transmitter and fled with her to the rebel baseship until order was restored. He persuaded Adama to arm his religious group as a counterweight to disorder, cementing his leadership of it. When the last Raptor left a doomed Galactica, Baltar chose to stay and finally do something noble, fighting as part of the reserve during the battle at the Cylon Colony. (Battlestar Galactica, "The Oath"; Battlestar Galactica, "Deadlock"; Battlestar Galactica, "Daybreak, Part II")
There Baltar and Caprica Six found Hera and carried her into the CIC, where his speech to the Cylon leader Cavil, in which he confessed that his atheism had given way to belief in unexplained, supernatural influence, helped Saul Tigh broker the truce that ended the war. On the new Earth, Baltar joined the survey crew and, observing Hera with Caprica Six, made peace at last with following in his father's footsteps as a farmer. (Battlestar Galactica, "Daybreak, Part II")
Frequently asked questions
- Who is Gaius Baltar in Battlestar Galactica?
- Dr. Gaius Baltar was an accomplished computer scientist of Aerilon descent whose ambition and political connections made him a celebrity advocate for re-introducing software networking to military vessels after the Cylon War. Manipulated by the Cylon agent later known as Caprica Six, he gave her access to the defense software she used to cripple the Colonial Fleet.
- How did Gaius Baltar doom the Twelve Colonies?
- Baltar became involved with a woman he believed worked for a defense contractor and gave her access to the highly classified Colonial defense mainframe. She covertly seeded the Colonial navigation program with backdoors, and when the Cylons attacked they used those backdoors to disable fighter squadrons and sabotage capital ships, killing billions in mere hours.
- How did Gaius Baltar become President?
- As Caprica's delegate to the Quorum of Twelve, Baltar was elected Vice President with Roslin's backing, then ran against her for the presidency. He was far behind in the polls until the accidental discovery of a habitable planet let him promise immediate settlement, an issue that swung the election.
- Why did Gaius Baltar surrender New Caprica to the Cylons?
- A year of settlement on New Caprica brought hardship, and when a Cylon fleet arrived in orbit Baltar accepted their delegation's terms and surrendered. He remained President only as a figurehead, forced at gunpoint to sign execution orders, though he repeatedly urged the Cylons that their occupation could not succeed.
- What happened to Gaius Baltar at the end of the war?
- Baltar chose to stay aboard a doomed Galactica to finally do something noble, and in the final battle he and Caprica Six found Hera and carried her into the CIC, where his speech to the Cylon leader Cavil helped Saul Tigh broker the truce that ended the war. On the new Earth he joined the survey crew and made peace at last with following in his father's footsteps as a farmer.
Sources
- EpisodeBattlestar Galactica (miniseries), Miniseries (2003)
- Episode33, Season 1, Episode 1 (2004)
- EpisodeWater, Season 1, Episode 2 (2004)
- EpisodeSix Degrees of Separation, Season 1, Episode 7 (2004)
- EpisodeThe Hand of God, Season 1, Episode 10 (2005)
- EpisodeColonial Day, Season 1, Episode 11 (2005)
- EpisodeEpiphanies, Season 2, Episode 13 (2006)
- EpisodeLay Down Your Burdens, Part II, Season 2, Episode 20 (2006)
- EpisodePrecipice, Season 3, Episode 2 (2006)
- EpisodeExodus, Part II, Season 3, Episode 4 (2006)
- EpisodeTorn, Season 3, Episode 6 (2006)
- EpisodeRapture, Season 3, Episode 12 (2007)
- EpisodeTaking a Break from All Your Worries, Season 3, Episode 13 (2007)
- EpisodeDirty Hands, Season 3, Episode 16 (2007)
- EpisodeCrossroads, Part II, Season 3, Episode 20 (2007)
- EpisodeEscape Velocity, Season 4, Episode 4 (2008)
- EpisodeThe Hub, Season 4, Episode 9 (2008)
- EpisodeThe Oath, Season 4, Episode 13 (2009)
- EpisodeDeadlock, Season 4, Episode 16 (2009)
- EpisodeDaybreak, Part II, Season 4, Episode 20 (2009)
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Followed from this entry

Head Six: the Number Six only Gaius Baltar can see
Head Six is the version of Number Six that lives in Gaius Baltar's head, talking, teasing and steering him for the whole of Battlestar Galactica. The show spends four seasons asking whether she's madness, a Cylon chip or something else, and the finale finally answers it.

Galen Tyrol
Chief Petty Officer Galen Tyrol kept Galactica's flight deck running through the long flight from the Colonies, a respected and fiercely protective deck chief who learned that he was in fact one of the Final Five Cylons, descended from the Thirteenth Tribe.

Hera Agathon
Hera Agathon was the first human-Cylon hybrid to exist, born to a Colonial officer and a Number Eight Cylon in the first month after the Fall of the Twelve Colonies. Held to be central to God's plan for both races, she was known before her birth as the Shape of Things to Come.

Laura Roslin: the dying leader
Secretary of Education until the Cylon attack killed everyone above her. Sworn in as President, she became the dying leader of Colonial prophecy.

Lee Adama: Leland Adama, callsign Apollo
Commander Leland "Apollo" Adama was a Colonial Fleet officer, the sole surviving son of William Adama, who served as Galactica's CAG before turning to politics as the Caprican delegate to the Quorum and, in time, interim President of the Twelve Colonies.

Saul Tigh
Colonel Saul Tigh was the executive officer of the battlestar Galactica and William Adama's oldest friend, a hard-drinking and embittered soldier who later discovered he was one of the Final Five Cylons yet never stopped thinking of himself as a Colonial officer.
Mentioned in65 entries
"33": Battlestar Galactica season 1 episode 1 explained
The fleet has been running for five days, jumping every 33 minutes with the Cylons right behind it. Here's what happens in "33", what it tells us about the Cylon plan, and which threads pay off later in the series.
"Crossroads": the Battlestar Galactica season 3 finale and Final Five reveal explained
"Crossroads" is the two-part season 3 finale: Gaius Baltar goes on trial for his time as president, four people hear a song nobody else can, and Starbuck comes back from the dead. Here's what happens and what it reveals.
"Daybreak": the Battlestar Galactica finale and ending explained
"Daybreak" is the two-part finale of Battlestar Galactica: one last rescue mission, a jump to a new world, and a final scene set in our own time. Here's what happens in Parts I and II, and what the ending means.
"Downloaded": Battlestar Galactica season 2 episode 18 explained
"Downloaded" is the episode told from the Cylon side, following Caprica Six and Boomer after they wake up in new bodies on occupied Caprica. Here's what happens, why Hera's "death" matters and how it sets up the season finale.
"Exodus": Battlestar Galactica season 3 episodes 3 and 4 explained
"Exodus" is the two-part escape from New Caprica: the resistance gets the launch keys, Galactica drops through the atmosphere and Pegasus is lost. Here's what happens in Parts I and II, and what the episodes reveal.
"Lay Down Your Burdens": the Battlestar Galactica season 2 finale explained
"Lay Down Your Burdens" is the two-part season 2 finale: a rescue mission to Caprica, a rigged election, a nuke on Cloud 9 and a jump of a whole year to the settlement on New Caprica. Here's what happens in Parts I and II and how it sets up season 3.
"Pegasus": Battlestar Galactica season 2 episode 10 explained
A second battlestar turns up alive, and its admiral outranks Adama. Here's what happens in "Pegasus", what it shows about Helena Cain and her crew, and how the standoff it ends on plays out.
"The Hub": Battlestar Galactica season 4 episode 9 explained
In "The Hub", humans and rebel Cylons destroy the Resurrection Hub and end Cylon immortality, while Roslin, stuck on a basestar with Baltar, finally hears his confession. Here's what happens, what Roslin's visions of Elosha mean and where it leads.
Aaron Kelly
Captain Aaron Kelly was the Landing Signals Officer aboard the battlestar Galactica and third in its chain of command. He served through the fall of the Twelve Colonies, the occupation of New Caprica, and the trial of Gaius Baltar, during which he turned to terrorism before recoiling from a later mutiny.
Admiral Nagala: the last commander of the Colonial Fleet
Admiral Nagala was the flag officer who took personal command of the Colonial Fleet after Picon Fleet Headquarters was destroyed in the opening barrage of the Fall. The admiral led a counterattack near Virgon that the Cylon corruption of the Command Navigation Program turned into a massacre, and died aboard Atlantia.
Adrasteia
Adrasteia was a civilian ship that escaped the Fall of the Twelve Colonies as part of the ragtag fleet. It was still listed among the fleet's ships at the first presidential election after the Fall.
Aerilon
Aerilon was an agricultural world and one of the Twelve Colonies of Kobol. Known as the food basket of the Colonies, it was a poor, working-class farming world and the birthplace of Gaius Baltar.
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