Karatsu, Saga
Due to its proximity to mainland Asia, Karatsu has long been known as a stopover to Korea and China.Under ritsuryō, the current city area was part of the Hizen Province. In 1591, on the coast of the northern part of the city (formerly the town of Chinzei), Nagoya Castle was constructed. The following year, it became the location from which the Imjin War was launched by Toyotomi Hideyoshi. In the middle of 1593, Terasawa Hirotaka created the Karatsu domain and began governing it. In 1602, replacing Nagoya Castle, Karatsu Castle was constructed in what is now the heart of Karatsu. The tower of Karatsu Castle was built in 1966 .
Oda clan
Nobuhide took Nagoya Castle in 1525 (it was given to Nobunaga in 1542), and built Furuwatari Castle. Oda Nobutomo held Kiyosu Castle, but he was besieged and killed in 1555 by his nephew Oda Nobunaga who operated from Nagoya Castle. This led to the family being divided into several branches, until the branch led by Oda Nobunaga eclipsed the others and unified its control over Owari.