A jinya is a residence where a government office was located of the domain (han) of a daimyo (territorial lord) under the shogunate system in the Edo period, or a building acting as the residence and office of the daikan (local governor) of a tenryo (bakufu-owned piece of land).
In general a daimyo with an income of less than 30,000 goku and didn't have a castle owned a jinya. A jinya also refers to a residence where the government office of the chigyosho, which is a domain of the bakufu hatamoto (direct retainers of the bakufu, a form of Japanese feudal government headed by a shogun) or karo (chief retainer) of a big domain, was located. Daimyo having an enclave domain occasionally set up a jinya as a local office in the enclave. In addition, Goryokaku and Nagasaki Magistrate's office are sometimes regarded as jinya. Also, the magistrate's office at shihaijo which was directly governed by the Edo bakufu (Japanese feudal government headed by a shogun) is considered a jinya in some cases.
When a mujo daimyo was promoted to joshu daimyo (governor of a castle) or joshukaku daimyo (daimyo without castle, but treated in a similar way to joshu daimyo), he was not allowed to convert his local jinya to a castle but actually was allowed to construct a gate only.
A jinya was easy to maintain compared to a castle and often had functions for administration and residence only. Within or outside the area enclosed by walls or nagaya (row houses) were residences called nagaya or koya (small houses) depending on the region, in which followers lived, a central office, and an inner part called the honjin.
Some jinya were built to the same height as a castle. Especially the daimyo jinya of small domains were built in imitation of a castle, for example Sonobe-jo Castle and Komono Jinya (Komono-cho, Mie Prefecture) were constructed towards the end of the Edo period (1868) with a turret likened to a tenshu (main keep or tower of a castle), a mizubori (water-filled moat), low stone walls, and dorui (earthworks), and also Mori Jinya (Kusu Town, Oita Prefecture) had many stone walls in the adjacent shrine and a two-storied chaya (tea house) which was likened to a tenshu. Some jinya had limited military functions such as Hekirichi Jinya of the Matsumae Domain (Kamiiso-cho, Hokkaido Prefecture) which had dorui and gun batteries in ryoho-shiki style (a style based on the fortification of Vauban in France).
Three major jinya
Iino Jinya in Kazusa Province, Tsuruga Jinya in Echizen Province, and Tokuyama Jinya in Suo Province are the three major jinya.
Jinya remaining today
Nabari Jinya (Mie Prefecture) is a daimyo jinya, or more precisely a jinya of the Nabari Todo family of the Todo clan.
Other functions of jinya
A jinya originally meant a tsumesho (guardroom) for an eji (guard) who guarded the palace in the Heian period.
(Derived from this, today some inns and hot springs are called 'jinya'). An example is Motoyu Jinya of Tsurumaki Onsen.
In the Kamakura period a jinya meant a temporary military camp for warriors during a battle.
An office of a jito (manager and lord of a manor) was also called a jinya.
In early-modern times a jinya indicated more a base of civil administration and became a word meaning a government office and residence or warehouse under the shogunate system.