The USS Essex was a 36-gun frigate that participated in the Quasi-War with France, the First Barbary War, and the War of 1812. She was very successful in disrupting British whaling in the Pacific, before being captured in 1814, and re-purposed as the HMS Essex under the Royal Navy.

Launched on 30 September 1799, she was armed with short ranged carronades that could not hope to match the range of 18 or 24 pounder naval guns. The US Navy accepted her nevertheless and under the captaincy of Edward Preble, holding the distinction of being the first US Naval ship to cross the Equator in early 1800.