According to the Records of Shiojiri Town, Nishijōjō was built by the Ogasawara, nominal rulers of Shinano Province, following the intra-clan conflict of the Suwa in 1449. The Ogasawara had supported the defeated side in that civil war and struggled to reinforce them, although the enemy had likewise struggled to push its advantage. The Ogasawara's main base at that time was Igawa Castle, and they were concerned about an invasion from Suwa, so Nishijōjō was built at a strategic midway point between Lake Suwa and Igawa Castle.
Nishijōjō's first commander was Ogasawara Masanori. Later the castle came to be occupied by Ogasawara Clan relatives and vassals, the Nishijō Clan, begetting its name, under the lords Nishijō Mitsumasa, Nishijō Mitsuyasu, Nishijō Sadayasu, and Nishijō Yorisada.
Nishijōjō is located at the top of a mountain, part of a network of fortifications consisting also of Arashi Castle and Iinawa Castle below it in that order. The ruins of Nishijōjō consist of horikiri (trenches), dorui (earthen ramparts) and the main bailey. To the rear of the main bailey is a large trench, about as tall and as wide (at the top) as a house. The views from up here are impressive.
|English Name||Nishijo Castle|
|Castle Condition||Ruins only|
|Historical Period||Pre Edo Period|
|Artifacts||Dorui, Hori, Kuruwa|
|Access||Midoriko Station on the Chuo Line; 10 minute walk to trail head|
|Visitor Information||24/7 free; mountain|
|Time Required||30 minutes|
|Location||Shiojiri, Nagano Prefecture|
|Coordinates||36° 4' 51.85" N, 137° 57' 56.81" E|
|Year Visited||Viewer Contributed|
|Added to Jcastle||2020|