Atakebune

Japan undertook major naval building efforts in the mid to late 16th century, during the Sengoku period, when feudal rulers vying for supremacy built vast coastal navies of several hundreds of ships.

[citation needed] Around that time, the Japanese daimyō Oda Nobunaga had made, according to the diary of the Abbot of the Tamon-I, six large iron-covered atakebune in 1578.

[1] However, in the letter from João Rodrigues to Luís Fróis in 1593, full iron-covered atakebune built by Toyotomi Hideyoshi were mentioned.

[2] Kanpaku (Hideyoshi) commanded them to build several huge ships.Their structure above the surface is fully covered by iron, and there is tower on the deck.

The Oda defeated the Mori's navy with them at the mouth of the Kizu River, Osaka in 1578 in a successful naval blockade.