Colonial One, a passenger starliner formerly known as Colonial Heavy 798, is now the residence and seat of government of the President of the Twelve Colonies. At the time of the Cylon attack, she was ferrying then-Secretary of Education Laura Roslin to the battlestar Galactica for its decommissioning ceremony. However, when word was recieved that President Adar and all 42 Cabinet-level officials above Roslin in line of presidential succession died, Roslin was sworn-in as President aboard the vessel, know identified by the presidential callsign Colonial One. After successfully escaping from the Cylons with a refugee fleet shepherded by Galactica, President Roslin set up her office on Colonial One and began trying to rebuild the civilian government from there. Roslin served out the remaining months of President Adar's term on Colonial One, before losing the presidential election to Dr. Gaius Baltar. President Baltar proceeded to order the fleet to colonize New Caprica, landing Colonial One on the planet, and remodelling it into his own egocentric bachelor pad.