18 March 1946 The United States begin the nuclear weapon test on the Bikini atoll using various captured and decommissioned warships as a target, including the Japanese battleship Nagato. On 1 July, the first nuclear weapon was detonated. On 25 July, the second nuclear weapon was detonated. The Nagato was located 900-1000 m from the epicenter. The blast heavily damaged the ship and contaminated with radioactivity.

In the end, on 4:00 AM of 29 July. The battleship Nagato was flooded and sunk benearth the Bikini atoll.