Savannah was begun in 1820 at the New York Navy Yard, but she remained on the stocks until 5 May 1842, when she was launched. She was one of nine frigates to be built from a prototype design by naval architect William Doughty. Savannah, with Captain Andrew Fitzhugh in command, joined the Pacific Squadron as flagship in 1844. As the prospect of war with Mexico became imminent, the Squadron moved into position off the California coast. On 7 July 1846, the Squadron captured Monterey without firing a shot. On 8 September 1847, Savannah returned to New York for repairs.