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In the continuation series project concept, produced by Tom DeSanto and Bryan Singer, the Fleet, tired of their space exodus, settle in an asteroid field. The new colony, New Caprica, is headed by a Council of Twelve lead by Mara, the Colonial president.
The Council directs the outmoded battlestar Galactica to be decommissioned. President Mara attends the decommissioning ceremonies aboard the battlestar. Just as Galactica is powered down, a heavily advanced version of the Cylons return to attack the colony.
In the Original Series, the Colonial president, Adar, dies when his flagship battlestar, Atlantia is destroyed during the Battle of Cimtar. The office of the president is never filled during the course of the series.
In the Re-imagined Series, the Colonial Secretary of Education, Laura Roslin, attends the decommissioning ceremonies for the outdated battlestar, Galactica, which is scheduled to be transformed into a museum of the Cylon War. After the Fall of the Twelve Colonies, Roslin becomes the new interim President of the Twelve Colonies.