The Atlanta-class cruisers were eight United States Navy light cruisers which were designed as fast scout cruisers or flotilla leaders but which proved to be effective anti-aircraft cruisers during World War II. They were also known as the Atlanta-Oakland class. The Atlanta class originally had 16 x 5-inch (127 mm)/38 caliber guns in eight two-gun turrets, arranged with three superfiring turrets forward, three more superfiring aft and two waist mounts, one port and one starboard, giving the first four Atlanta-class cruisers the heaviest anti-aircraft armament of any cruiser of World War II. The last four ships of the class, starting with Oakland, had a slightly revised armament with a reduced main gun battery - the waist turrets being deleted - as they were further optimized for anti-aircraft fire in light of war experience.

A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to this smaller cruisers had been of the protected cruiser model, possessing armored decks only. While lighter and smaller than other contemporary ships they were still true cruisers, retaining the extended radius of action and self-sufficiency to act independently around the world. Cruisers mounting larger guns and heavier armor relative to most light cruisers would come to be known as heavy cruisers, though the designation of 'light' versus 'heavy' cruisers would vary somewhat between navies. Through their history light cruisers served in a variety of roles, primarily as convoy escorts and destroyer command ships, but also as scouts and fleet support vessels for battle fleets.