Cyane was launched 2 December 1837 by Boston Navy Yard. She was commissioned in May 1838, Commander John Percival in command. She sailed 24 June 1838 for duty in the Mediterranean, returning to Norfolk, Virginia 16 May 1841. She cleared 1 November 1841 for the Pacific Squadron, returning 1 October 1844. Sailing again for the Pacific 10 August 1845, Cyane served on the west coast during the Mexican War. On 7 July 1846 her commanding officer, Captain William Mervine, led a detachment of Marines and sailors from Commodore John D. Sloat's squadron ashore at Monterey, California, hoisting the American flag at the Customs House and claiming possession of the city and all of present day California.