Nagoya Castle was constructed under the order of Tokugawa Ieyasu who founded the Tokugawa Shogunate after the battle of Sekigahara and resolved in 1609 to move from Kiyosu to build a castle in Nagoya in order to secure an important position on the Tokaido highway and to ward off attacks from the direction of Osaka. Construction of the donjons began in 1610 and ended in 1612. Nagoya Castle is an exemplary castle of those built on flat lands. — from the entrance billboard of Nagoya Castle