Atakebune

Atakebune (安宅船^?) were large Japanese warships of the 16th and 17th century used during the internecine Japanese wars for political control and unity of all Japan.

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. The largest (and generally most dangerous) of these ships were called Atakebune.

Around that time, the Japanese daimyo Oda Nobunaga had made, according to the diary of the Abbot of the Tamon-I, six iron-covered big Atakebunes in 1578. These ships were called "Tekkōsen" (), literally meaning "iron ships", which is not to imply they were of iron, but that their superstructure may have been reinforced with iron plates against cannon and fire arrows. No iron-covering at all, however, was mentioned in the account of the Jesuit missionary Luis Frois, who had also seen and described the ships. Abbot of the Tamon-I　did not witness the ships actually, so the existence of the iron plates is questioned.

However, in the letter from João Rodrigues to Luís Fróis in 1593, full iron-covered Atakebune build by Toyotomi Hideyoshi was mentioned. Hideyoshi made those ships to invade Korea and their superstructure was fully covered by iron plates.

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. Bridges are covered by iron, and no wood is exposed. And whole parts are gilded very beautifully. These were worth admiring, I sometimes entered in the ships. I measured the length of one there, it was 19 jou(36.3 meter) long. These ships astonished several Portuguese who looked inside. However, these ships were frangible due to defective ribs. So some of them cleaved and sank.

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Wikipedia