Obi district was originally a Fujiwara
Shōen that was developed in the
Heian period. It was located at a strategic location, with the important ports of Aburatsu (油津) and Sotonoura (外之浦) to the south, and the second largest city in this region,
Miyakonojō, to the west. Obi Castle was built on a hill in the
Shirasu Plateau to the north of Obi district. The history of the castle is not clear, but it is believed that the Obi-in (office), one of the eight districts of
Hyūga, that was placed in the manor during the manor period was the origin of the castle. Obi District is surrounded by a Sakatani river on three sides: east, west, and south. The south side of the Sakatani river, the east side, and the north side of the castle are surrounded by mountains and hills, making Obi District a natural fortress in a basin shape. In the late
Muromachi period, in 1458, the
Shimazu clan, which was based in the south of Kyushu, sent their vassal, Niiro Tadatsugu, who was the lord of
Shibushi Castle, to Obi Castle in preparation for the invasion of the south of Kyushu by the Ito clan. In 1484, the Ito clan attacked Obi, and since then, the battle for Obi between the Ito clan and the Shimazu clan continued for about 100 years. In 1587,
Toyotomi Hideyoshi conquered Kyushu, and
Itō Suketaka was awarded Obi Castle for his achievements. Since then, the Ito clan has ruled Obi Domain as a castle town with 51,000
Koku (石) for 14 generations for about 280 years until the
abolition of the han (feudal) system in 1871 during the
Meiji period. Obi Castle was a medieval castle of the old type that used the natural terrain of the Shirasu Plateau. The castle was severely damaged by a major earthquake in 1684, but it was rebuilt in a modern style of Edo period with the use of stone walls. These stone walls still remain today. However, when looking over the entire castle layout, many parts still retain their natural terrain. Obi Domain had a vast mountain range and a long coastline, but it had little flat land, so there was little good farmland and the production of agricultural products was low. As a result, the domain could not expect to earn revenue from agricultural products. Obi district was blessed with abundant forest resources, so the forest resources played a major role as the domain's main monopoly product in order to raise funds for the renovation of Obi Castle and the renovation of rivers. Obi district is a humid area, so the cedar trees in Obi grow quickly and have a lot of oil, making them light and elastic. These characteristics made them ideal for shipbuilding, and they became known throughout Japan. By 1800, the mountains within the domain of Obi had been transformed into cedar forests through the domain's reforestation efforts. The Obi cedar trees played a crucial role in supporting the domain's financial resources. The Meiji Restoration resulted in the abolition of the han (feudal) system in 1871 and the demolition of all the buildings in Obi Castle. From the Meiji period to the 1960s, the Obi district experienced a prolonged economic boom, primarily driven by the cedar trees planted during the Edo period. In 1950, the towns of Obi, Agata, Aburatsu, and Togō, which were divided into small administrative districts, merged to become the former Nichinan City. The city of Nichinan began a restoration project of Obi Castle in 1974 to attract tourists. and the city's territory became nearly the same as it was during the Edo period as the Obi domain.
Jōkamachi Itō Suketaka, who became the first lord of Obi Domain, immediately began the construction of the Jōkamachi (castle town) of Obi. According to the ancient document "Hyuga-ki (日向記)," this was recorded to have taken place in 1599 when urban planning and division of plots were carried out. Initially, the retainers of Obi Domain lived scattered in areas such as Kiyotake, Sakatani, and Nango. However, in 1615, the
Tokugawa Shogunate established a system where each domain could have only one castle. As a result, the retainers moved to the Obi Castle town, which further accelerated the construction of the castle town. The width of the streets in the castle town has been maintained since the early Edo period. As a result, the gates, stone walls, and hedges that face the streets have also been well preserved in the same condition as the Edo period. Samurai residences featured gates corresponding to their social status, and they constructed buildings and stone walls using local materials such as Obi cedar and Obi stone. A characteristic feature is the planting of hedges, such as tea hedges, on top of these stone walls. After the Meiji Restoration, many of the samurai residences saw changes in occupants, and the buildings were rebuilt and the large grounds were divided into smaller plots. However, the majority of the divisions and streets still retain the characteristics of the early Edo period and have been preserved to the present day. == Obi Castle restoration project ==