Korean-style fortresses in Japan

Over the course of the Yamato period, in the early centuries of the establishment of a Japanese state, a great number of Korean-style fortresses (朝鮮式山城, Chōsen-shiki yamajiro) were constructed in Japan.

Many of these sites have been identified with fortresses whose construction, repair, and destruction are described in detail in ancient chronicles such as Nihon Shoki and Shoku Nihongi.

Research on these sites is ongoing, and the questions of the purposes and origins of the fortresses, and their possible connections to Korea remain hotly debated among scholars, in part due to the nationalistic elements involved.

"old period mountain castle/fortresses") is sometimes used, but its opponents argue that it can be interpreted too broadly; Chōsen-shiki yamajiro, even if not an entirely accurate description, denotes a very particular group of sites.

However, mainstream sources such as newspapers and magazines, continue to represent the widely believed "traditional" version of events put forward by older scholarship, and to use the Korean-related terminology.