Founded sometime in the Kamakura Period, Oko Castle was the original base of power for the Chosokabe Clan. In 1509 Motoyama Motoshige captured the castle but after reaching an agreement with the Chosokabe it was returned in 1511. In 1585, Chosokabe Motochika unified Shikoku from Oko Castle. Later that same year Hideyoshi invaded Shikoku. Chosokabe surrendered to Hideyoshi and was allowed to keep his home domain of Tosa. The Chosokabe moved their home castle from Oko Castle to Otakasaka Castle, which was on the site of the current Kochi Castle in 1588, but due to poor conditions they soon moved back to Oko Castle. In 1591 they moved to their final castle Urado Castle and abandoned Oko Castle.
The Kochi Prefectureal Museum of History is located on part of the former castle grounds.
|English Name||Oko Castle|
|Year Founded||13-14th Century|
|Castle Condition||Ruins only|
|Designations||Next 100 Castles, Top 100 Mountaintop Castles, National Historic Site|
|Historical Period||Pre Edo Period|
|Features||trenches, stone walls|
|Access||Kochi Sta., 25 min bus|
|Location||Nangoku, Kochi Prefecture|
|Coordinates||33° 35' 42", 133° 37' 21"|
|Year Visited||Viewer Contributed|
|Added to Jcastle||2013|