The discovery of the wreck of the USS Juneau off Solomon Islands has been described as hugely significant.
The light cruiser was sunk by a torpedo on Friday 13 November, 1942, during the Battle of Guadalcanal, with all bar 10 of the 687 crew losing their lives.
The discovery of the Juneau comes just weeks after a crew, also funded by the philanthropist Paul Allen, found wreckage from the USS Lexington - a US aircraft carrier sunk by the Japanese - about 800 kilometers off the Australian coast.
Dave Werner of the US Pacific Fleet said the Juneau was one of 13 US ships lost during the ultimately successful battle to stop the Japanese replenishing their troops on Guadalcanal.
He said the Juneau crew included the five Sullivan brothers who had volunteered after the Pearl Harbor attack and wanted to serve on the same ship.
"Initially the Navy reportedly declined their offer, for obvious reasons. They didn't them serving together in hazardous duty. Ultimately, because of the needs of the war the brothers were allowed to serve together, and of course, all five did perish."
In 1943 the US Navy commissioned a destroyer called the USS Sullivans, in honour of the brothers.