Battleship Nagato in the early 1920s Nagato named after Nagato province) was a battleship of the Imperial Japanese Navy; the lead ship of her class. She was the first battleship in the world to mount 16 inch (actually 16.1 inch, or 410 mm) guns, her armor protection and speed made her one of the most powerful capital ships at the time of her commissioning. She was the flagship of Admiral Isoroku Yamamoto at the time of the attack on Pearl Harbor. She participated in a number of naval actions, but fired her main armament against enemy surface vessels only once, during the Battle of Leyte Gulf. She survived the war and was sunk by the underwater nuclear test BAKER at Bikini Atoll in 1946.