Izaku Castle (伊作城 Izaku-jō) is a castle complex in the town of Hioki, Kagoshima Prefecture, that was constructed in the 13th century. It served as the headquarters of the Shimazu clan until 1536 when Shimazu Takahisa relocated his base to Ichiūji Castle. (一宇治城)
Izaku Castle itself was constructed in the 13th century by Shimazu Hisanaga (島津久長), the first head of the Izaku Shimazu branch, on the western part of Satsuma Peninsula. Under the 10th clan head Tadayoshi (島津忠良, 1493-1568) the influence of the Izaku clan significantly expanded. His son Takahisa (島津貴久, 1514-1571), born at Izaku Castle, was adopted by Shimazu Katsuhisa (島津勝久, 1503-1573) and became the 15th head of the Shimazu clan.
In the succession conflict of the 1520s, Shimazu Sanehisa (島津実久, d.1553), an illegitimate offspring of the Sasshū branch of the clan who had become the lord of Izumi Castle (出水城), joined Katsuhisa and attacked Kagoshima Castle (鹿児島城) to expel Katsuhisa's adoptive heir Takahisa. He gradually expanded his power, defeating and banishing Niiro Tadakatsu (新納忠勝, 1491-1549) from the Shibushi area, and earning the title of "lord of three provinces". Meanwhile, Katsuhisa fled to Chōsa in the province of Ōsumi and turned against Sanehisa. The Sōshū-Shimazu forces attacked those of Sanehisa in Ichiūji Castle in 1536 and the following year joined forces with Katsuhisa. Although Sanehisa had managed to keep the Sōshū-Shimazu at bay for some time, Takahisa and his father Shimazu Tadayoshi gradually expanded their territory; Sanehisa also fought with the Iriki-in clan and in 1539 suffered a series of defeats in Kaseda, Ichiki, Kawanabe and Murasakibaru, and was eventually driven out of Kagoshima. Takahisa was finally recognized as lord of the three provinces (Satsuma, Osumi, and Hyūga) in 1545.
Izaku castle was abandoned in 1615.
Izaku Castle is typical for Kagoshima castles: it is located on a shirasu-daichi (シラス台地, pyroclastic plateau) and made use of moats formed by curved valleys and plateaus for enclosures. The main enclosure (also called 亀丸城, Kamemaru Castle) was at the centre, and Kura-no Castle (蔵之城) and Higashi-no Castle (東之城) at the eastern side, Nishi-no Castle (西之城) and Hanami Castle (花見城) at the west side, and Yama-no Castle (山之城) at the southern side.
Based on a map of the Geospatial Information Authority of Japan. The location of the enclosures is estimated.
I rented a car and embarked on a tour of castles situated on the Satsuma Peninsula. To reach Izaku Castle, I turned north on Izaku Highway (Prefectural Route 22) and followed the signs to Kamemaru Castle. There is a parking lot next to the castle.
I first circled the enclosures from the east.
The entrance to Higashi-no Castle (東ノ城虎口 Higashi-no-jō koguchi)
Trenches between the enclosures
① The Eastern Castle (東ノ城 Higashi-no-jō)
It was quite obvious that it was not maintained very well.
Those massive ferns covering the cliff of sirasu daichi are typical for Kagoshima castles.
② Kurano Castle (蔵之城)
Judging by its name, this might have been the location of the storage house.
The path to the main enclosure (本丸 Honmaru).
③ The main enclosure (本丸 Honmaru).
Eminent Shimazu family members including the Lord of Nissin, Yoshihisa and Yoshihiro were born in this castle. Their birthstones were erected in the Honmaru.
I went to visit Okariya Castle and Nishi-no Castle in the west. But any special remains were found there. (below photographs of Okariya Castle and Nishi-no Castle)
Outline of the castle complex
Date of visit: 19 October 2013
History:
Izaku Castle itself was constructed in the 13th century by Shimazu Hisanaga (島津久長), the first head of the Izaku Shimazu branch, on the western part of Satsuma Peninsula. Under the 10th clan head Tadayoshi (島津忠良, 1493-1568) the influence of the Izaku clan significantly expanded. His son Takahisa (島津貴久, 1514-1571), born at Izaku Castle, was adopted by Shimazu Katsuhisa (島津勝久, 1503-1573) and became the 15th head of the Shimazu clan.
In the succession conflict of the 1520s, Shimazu Sanehisa (島津実久, d.1553), an illegitimate offspring of the Sasshū branch of the clan who had become the lord of Izumi Castle (出水城), joined Katsuhisa and attacked Kagoshima Castle (鹿児島城) to expel Katsuhisa's adoptive heir Takahisa. He gradually expanded his power, defeating and banishing Niiro Tadakatsu (新納忠勝, 1491-1549) from the Shibushi area, and earning the title of "lord of three provinces". Meanwhile, Katsuhisa fled to Chōsa in the province of Ōsumi and turned against Sanehisa. The Sōshū-Shimazu forces attacked those of Sanehisa in Ichiūji Castle in 1536 and the following year joined forces with Katsuhisa. Although Sanehisa had managed to keep the Sōshū-Shimazu at bay for some time, Takahisa and his father Shimazu Tadayoshi gradually expanded their territory; Sanehisa also fought with the Iriki-in clan and in 1539 suffered a series of defeats in Kaseda, Ichiki, Kawanabe and Murasakibaru, and was eventually driven out of Kagoshima. Takahisa was finally recognized as lord of the three provinces (Satsuma, Osumi, and Hyūga) in 1545.
Izaku castle was abandoned in 1615.
Izaku Castle is typical for Kagoshima castles: it is located on a shirasu-daichi (シラス台地, pyroclastic plateau) and made use of moats formed by curved valleys and plateaus for enclosures. The main enclosure (also called 亀丸城, Kamemaru Castle) was at the centre, and Kura-no Castle (蔵之城) and Higashi-no Castle (東之城) at the eastern side, Nishi-no Castle (西之城) and Hanami Castle (花見城) at the west side, and Yama-no Castle (山之城) at the southern side.
Based on a map of the Geospatial Information Authority of Japan. The location of the enclosures is estimated.
Visiting the castle:
I rented a car and embarked on a tour of castles situated on the Satsuma Peninsula. To reach Izaku Castle, I turned north on Izaku Highway (Prefectural Route 22) and followed the signs to Kamemaru Castle. There is a parking lot next to the castle.
I first circled the enclosures from the east.
The entrance to Higashi-no Castle (東ノ城虎口 Higashi-no-jō koguchi)
Trenches between the enclosures
① The Eastern Castle (東ノ城 Higashi-no-jō)
It was quite obvious that it was not maintained very well.
Those massive ferns covering the cliff of sirasu daichi are typical for Kagoshima castles.
② Kurano Castle (蔵之城)
Judging by its name, this might have been the location of the storage house.
The path to the main enclosure (本丸 Honmaru).
③ The main enclosure (本丸 Honmaru).
Eminent Shimazu family members including the Lord of Nissin, Yoshihisa and Yoshihiro were born in this castle. Their birthstones were erected in the Honmaru.
I went to visit Okariya Castle and Nishi-no Castle in the west. But any special remains were found there. (below photographs of Okariya Castle and Nishi-no Castle)
Outline of the castle complex
Date of visit: 19 October 2013
Access:
- Address: Fukiage-cho Nakahara, Hioki-shi, Kagoshima
- Access: 14 kilometres from Ibusuki Road Taniyama Interchange via Prefectural Route 22
- Parking: next to the castle (spot 'P' on the above map)
- Other sights: Ichiūji Castle