Koromo Castle

Overview

Koromo Castle (挙母城, Koromo-jō) was a Japanese castle in what is now the city of Toyota, in Aichi Prefecture. It was founded in 1782, in the second year of the Tenmei era (天明, Tenmei, 1781–1789), during the Edo period (1603–1868). At the end of the Edo period the castle was the seat of the Naitō clan, the daimyō (大名, daimyō, territorial lords) of Koromo Domain (挙母藩, Koromo-han). The castle was also known as Shichishū-jō (七州城, Shichishū-jō).

History

Koromo Castle dates its foundation to 1782, placing its construction late in the Edo period, more than a century and a half after the Tokugawa shogunate was established in 1603. The castle served as the administrative and military centre of Koromo Domain, the feudal territory governed from the site.

By the closing decades of the Edo period, the castle was home to the Naitō clan, the daimyō family of Koromo Domain. As the domain's headquarters, the castle anchored the local government of the surrounding area in what is today Toyota, Aichi Prefecture.

What Stands There Today

The castle's site lies within the modern city of Toyota, Aichi Prefecture, at coordinates 35.0798833, 137.1504611. Toyota is the city that grew up around the old castle town, and the castle's location is now part of the urban fabric of the city.

The Name in Japanese

The castle's principal name is written 挙母城. Its kana reading is きょぼじょう, and its romaji form is Koromo-jō. The same name is also given the reading しちしゅうじょう for the alternative name Shichishū-jō, written 七州城.

Breaking down 挙母城 character by character:

• 挙 — read here as こ (ko). The character means "to raise," "to lift up," or "to nominate." In this name it functions as a phonetic element rather than carrying its literal meaning.
• 母 — read here as ろも (romo). The character means "mother." As with 挙, it is used here for its sound, not its sense; together 挙母 spell out the place name Koromo.
• 城 — read here as じょう (jō). The character means "castle" or "fortress." It is the standard suffix attached to the name of a Japanese castle, so 挙母城 is literally "Koromo Castle."

The alternative name 七州城 (Shichishū-jō) is built differently. 七 (しち, shichi) means "seven," 州 (しゅう, shū) means "province" or "state," and 城 (じょう, jō) again means "castle" — so the alternative name reads as "Castle of the Seven Provinces."

Visiting and Context

Koromo Castle stood in Toyota, Aichi Prefecture, a city in the Chūbu region of central Honshu. The castle's history is bound up with the Edo-period domain system: Koromo Domain was governed from the castle, and the Naitō clan held it as daimyō at the end of the Edo period.

For readers studying Japanese, the castle's names offer a compact lesson in how Japanese place names work. The characters 挙母 are read Koromo as a unit, a reminder that kanji in proper nouns often carry readings unrelated to their everyday meanings. The suffix 城 (じょう, jō) recurs across Japanese castle names, and the alternative 七州城 shows how a single site can carry more than one name, each with its own reading and its own logic.