USS Nautilus, a 2730-ton Narwhal class cruiser submarine, was built at the Mare Island Navy Yard, California. Commissioned in July 1930 as USS V-6 (SC-2), she was renamed Nautilus in February 1931 and redesignated SS-168 in July 1931. Prior to World War II, she was mainly operated in the Pacific, based at Pearl Harbor and at San Diego. Modernized between July 1941 and April 1942, her first war patrol included intense involvement in the Battle of Midway, during which she attacked a Japanese aircraft carrier that was at that time identified as Soryu but was more probably Kaga. Later during that patrol, while off Japan, she sank the destroyer Yamakaze.

Nautilus then began an active career as a transport submarine, a role for which her large size made her especially useful. She landed Marines to raid Makin Island, in the Gilbert Islands in August 1942; put scouts ashore at Attu, in the Aleutians, in May 1943; again landed Marines in the Gilberts in November 1943 and carried out several missions into the Philippines area in May 1944 - January 1945. During this time Nautilus also conducted anti-shipping and reconnaissance patrols off Japan, in the Central Pacific and in the Solomons area, sinking and damaging several Japanese ships. Ordered home after her 14th war patrol, she arrived at Philadephia, Pennsylvania, in May 1945 and was decommissioned the following month. Nautilus was sold for scrapping in November 1945.