144.Ogaki Castle Part1

A castle which might have been a crucial battle field

Location and History

Battlefield of Crucial Event

The Battle of Sekigahara have been one of the most crucial events in the Japanese History. The East squad led by Ieyasu Tokugawa and the West squad led by Mitsunari Ishida battled each other at Sekigahara Field in 1600 before the Tokugawa Shogunate was established. Most Japanese people know about Skigahara, but what about Ogaki Castle? In fact, the castle might have become the battle field of the crucial event if the situation changed (if Mitsunari decided to stay in that castle).

The Portrait of Ieyasu Tokugawa, attributed to Tanyu Kano, owned by Osaka Castle Museum (licensed under Public Domain via Wikimedia Commons)
The portrait of Mitsunari Ishida、 owned by Hajime Sugiyama (licensed under Public Domain via Wikimedia Commons)

Ogaki Castle as Important Point

Ogaki Castle was located in the western part of Mino Province (now Gifu Prefecture) connecting to western Japan trough Sekigahara. It is uncertain when the castle was first built, but it became important as the country had been unified in the late 16th Century during the Sengoku Period. The ruler, Hideyoshi Toyotomi said “Ogaki Castle is an important point” and actually sent his relatives to the castle as its lords. The castle was built on a plain land, but surrounded by several moats and rivers, which looked like a Water Castle.

The location of the castle

After Hideyoshi died in 1598, a political conflict began between Ieyasu Tokugawa and Mitsunari Ishida. Mitsunari doubted Ieyasu would take over the power of Hideyoshi’s young son, Hideyori who was still the ruler of Japan. Ieyasu went to eastern Japan to conquer the Uesugi Clan who were against Ieyasu in June 1600. Mitsunari raised an army to defeat Ieyasu in July in western Japan. The East and West squads were expected to fight in central Japan including Ogaki Castle and Sekigahara. Mitsunari stayed in Ogaki Castle as his stronghold and built several battle castles, such as Nangusan Castle, on the mountains behind Ogaki Castle for his allies to stay. He was waiting for Ieyasu’s attack at the castle doing as best as he could. He also built large mountain castles such as Matsuoyama Castle around Sekigahara Field to call for a great warlord, Terumoto Mori and his master, Hideyori to support him. If his plans came true, Ieyasu might have been defeated because Hideyori was still Ieyasu’s master as well.

The portrait of Hideyori Toyotomi, owned by Yogenin Temple (licensed under Public Domain via Wikimedia Commons)

Why did Mitsunari leave Castle?

However, on September 15th, Mitsunari suddenly got away from the castle, fought against Ieyasu at Sekigahara Field, and defeated in a day. Why did Mitsunari cancel his own plan and choose the field battle he probably dislike but Ieyasu was more familiar with? The long-accepted theory says Mitsunari noticed Ieyasu tried to skip Ogaki Castle and attack western Japan directly. Mitsunari and his allies were one jump ahead of Ieyasu, and took up their positions at the field. They fought well in the first part, but finally got defeated by the betrayal of Hideaki Kobayakawa, one of their allies, during the battle. This story is dramatic, so Japanese people believed it for a long time. However, it was first seen in war chronicles in the Edo Period, about 60 years later than the actual battle. I also think the reason above is too weak for Mitsunari to leave the castle.

The portrait of Hideaki Kobayakawa, owned by Kodaiji Temple (licensed under Public Domain via Wikimedia Commons)

Some new studies may tell us the real reasons why Mitsuhide left Ogaki Castle. According to these studies, Hideaki Kobayakawa was expected to support the East quad earlier than what the previous theory says. Hideaki occupied Matsuoyama Castle and moved to Sekigahara Field before the battle against Mitsunari’s plan. If he stayed, he could have been attacked on both sides. Mitsunari might have noticed Hideaki’s movement, so this may be why he quickly moved to Sekigahara to avoid the worst situation. One theory says Mitsunari tried to get to another mountain castle, called Tama Castle, to fight against Ieyasu and Hideaki, but was unfortunately defeated around Sekigahara Field. After the battle, some Mitunari’s retainers still stayed in Ogaki Castle, however, they were outnumbered. They surrendered after being besieged by the East squad for about a week.

The folding screens of the Sekigahara Battle, owned by Sekigahara Town History and Folklore Museum (licensed under Public Domain via Wikimedia Commons)

Ogaki as City of Water

After the Battle of Sekigahara, Ogaki Castle was still recognized as an important point connecting eastern and western Japan. Several different lords governed and improved the castle. For example, the Ishikawa Clan completed the Outer Moat and the Matsudaira Clan renovated the four-level Main Tower. The tower was in the Main Enclosure which is connected with the Second Enclosure where the Main Hall for the lord was. Both enclosures were surrounded by the Inner Moat. Overall, the tripled moats surrounded the castle. In addition, the castle town was consolidated with the castle by waterways and rivers. That’s why Ogaki City has been called The city of water. Since 1635, the Toda Clan governed the castle and the area was called the Ogaki Domain until the end of the Edo Period.

The four-level Main Tower of Ogaki Castle, from the signboard at the site
Part of the illustration of Ogaki Castle in Mino Province, exhibited by the National Archives of Japan
The center of Ogaki Castle, from the illustration above
The statue of Ujikane Toda, the founder of the clan in the Ogaki Domain

To be continued in “Ogaki Castle Part2”

144.大垣城 その1





徳川家康肖像画、加納探幽筆、大阪城天守閣蔵 (licensed under Public Domain via Wikimedia Commons)
石田三成像、杉山丕氏蔵 (licensed under Public Domain via Wikimedia Commons)





豊臣秀頼肖像画、養源院蔵 (licensed under Public Domain via Wikimedia Commons)



小早川秀秋肖像画、高台寺蔵 (licensed under Public Domain via Wikimedia Commons)


「関ヶ原合戦図屏風」、関ケ原町歴史民俗資料館蔵  (licensed under Public Domain via Wikimedia Commons)





38.Iwamura Castle Part3

Be careful choosing your parking spot.


Going to Main Enclosure, Center of Castle

The map around the Main Enclosure

From the Eastern Enclosure, you can enter the Main Enclosure by passing through two gate ruins and the Nagatsubone Enclosure between them.

The past Eastern Enclosure (front) and Nagatsubone Enclosure (back), drawn in the signboard at the site
The present Eastern Enclosure
The Nagatsubone-uzumi-mon Gate Ruins, the entrance of the Nagatsubone Enclosure
The long and narrow Nagatsubone Enclosure
The Front Gate Ruins of the Main Enclosure, the exit of the Nagatsubone Enclosure
The Front Gate Ruins seen from the inside of the Main Enclosure

The inside of the Main Enclosure is a square now. You can see from there views of the city area far away and the castle area around such as the Demaru Enclosure which also protected the Main Enclosure, but it is now used as a parking lot.

The past Main Enclosure, drawn in the signboard at the site
The inside of the Main Enclosure
A view from the Main Enclosure
The past Demaru Enclosure, drawn in the signboard at the site
A view of the Demaru Enclosure seen from the Main Enclosure
A side view of the Demaru Enclosure

You can also see the Uzumi-mon Gate Ruins which is the entrance from the Second Enclosure. It is interesting to see the stones on the steps are all cut in the shape of a triangle.

The past Uzumi-mon Gate, drawn in the signboard at the site
The Uzumi-mon Gate Ruins
The stones on the steps cut in the shape of a triangle

Later History

After the Meiji Restoration, Iwamura Castle was abandoned and all the buildings of the castle excluding the Main Hall at the foot were demolished. The hall was also burned by a fire in 1881. Iwamura History Museum opened in 1972 at the site of the former hall and part of the hall was also restored in 1990. On the mountain side, Ena City, which owns the ruins, recently excavated and researched them to develop and preserve them. The city aims to someday make the ruins designated as a National Historic Site.

Iwamura History Museum
The partly restored Main Hall (taken by HiC from photoAC)

My Impression

When I visited the ruins of Iwamura Castle, I made a mistake choosing my parking spot. I wanted to walk around the ruins from the foot to the top. However, my car navigation system led me to the parking lot near the top automatically. Therefore, I had to climb down to the foot first, then I returned back to the top. For visitors who want to see the entire ruins should park at the foot. If you want to see only the great stone walls on the top, you can park at the Demaru Enclosure, which is few minutes on foot from the Main Enclosure on the top.

The parking lot in the Demaru Enclosure
The Six Tier Stone Walls near the top

How to get There

I recommend using a car when you visit the castle ruins.
It is about a 20-minute drive away from Ena IC on the Chuo Expressway. There are two parking lots near the top and at the foot of the ruins
If you want to use public transportation, It takes about 30 minutes on foot from Iwamura Station on the Akechi Railway to arrive at the foot.
To get to Iwamura Station from Tokyo or Osaka: Take the Tokaido Shinkansen super express, transfer to the Chuo Line at Nagoya Station and transfer to the Akechi Railway at Ena Station.

That’s all. Thank you.
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