Roots of Japan

Japanese Castle

We can find “Oshiro”, or castles, in countries all over the world.

“Oshiro” were built for a number of reasons, for protection and defense, or as residences for feudal lords. Castles share these similarities across the globe. However, the appearance of the castle differs depending on the local culture, environment and surrounding nations. Today, let's turn our focus to the Japanese “Oshiro” and its history and origins.

First, why were “Oshiro” built?

Rice began to be cultivated in Japan around 3,000 years ago. The crops brought stability to the people but at the same time, conflict would arise within the community over the harvest. In order to protect themselves from conflict, they surrounded themselves with deep moats and earthen embankment walls built from the earth dug out of the moats.
These were called “kango-shuraku” or, moated settlements.

So, the roots of “Oshiro” go back a very long way. The Yoshinogari Ruins in Saga prefecture may be far from what you imagine when you hear the word “Oshiro” but they are actually included as one of the top 100 castles in Japan.

These kinds of village communities gradually declined and the people united into one country. In 664, Mizuki Castle in the ancient Tsukushi Province (presently situated across Dazaifu / Ōnojō / Kasuga in Fukuoka Prefecture) was built by the Emperor of the time. This is the first appearance of the word “Oshiro”, however there were many more “Oshiro” of this period that were not included in literature.

With each passing era, an increasing number of “Oshiro” were built, both small and large, reaching upwards of 40,000 to 50,000. Castle construction reached its peak during the 1500's and 1600's. In 1615, after the “Law of One Castle per Province” was enforced, only one castle for the feudal lord or one government office was allowed. As all others were abandoned, the result was that the number of remaining castles fell sharply to just 170!

Later, amid the chaos of the changing eras and the issuance of the “Ordinance for the Disposal of Castles” in 1873, “Oshiro” continued to disappear. While it is said that about two thirds did survive, they were often used as government offices or military buildings. The only “Genzon Tenshu” or remaining original castle keeps built in the Edo period (1603 - 1868 or earlier, and that have been preserved until today) are the following 12.

1/ Hirosaki castle (Aomori Prefecture) 2/ Matsumoto Castle (Nagano Prefecture) 3/ Maruoka Castle (Fukui Prefecture) 4/ Inuyama Castle (Aichi Prefecture)
5/ Hikone Castle (Shiga Prefecture) 6/ Himeji Castle (Hyogo Prefecture) 7/ Matsue Castle (Shimane Prefecture) 8/ Bitchū Matsuyama Castle (Okayama prefecture)
9/ Marugame Castle (Kagawa Prefecture) 10/Matsuyama Castle (Ehime Prefecture) 11/ Uwajima Castle (Ehime Prefecture) 12/ Kōchi Castle (Kochi Prefecture)

Shouldn't there be more left? There are several reasons why there aren't.

First, earthquakes. While Japan, a highly earthquake–prone country, now has many earthquake-proof buildings, much damage had already occurred up to this point. Many documents recording these events remain until today. An example still fresh in everyone's mind would be the damage to Kumamoto Castle caused by the 2016 Kumamoto earthquake.

Other reasons cited include fire damage, lightning strikes etc. War is yet another reason. Japan's national treasure “Oshiro” were subject to destructive air raids, due to the fact they were used as army garrisons. It is believed that in just four months eight castles were destroyed by fire.

Locals carried out restoration and reconstruction work but when the original architectural drawings were unrecoverable they would confirm details by comparing the height to other “Oshiro” and by using photographs etc. As result, we can now see about 100 castles in Japan.

In addition to “Genzon Tenshu” (original castle keeps), there are “Fukugen Tenshu”, restored Tenshu, “Fukko Tenshu”, reconstructed Tenshu and “Mogi Tenshu”, imitation Tenshu. You may enjoy researching which of these you would like to visit.

How are Japanese “Oshiro” built? Natural hilltop fortresses that took advantage of the mountainous terrain were built for defensive purposes. “Ishigaki”, stone walls, and moats also prevented invasion from enemies. These “ishigaki” walls are a fine example of earthquake resistant architecture unique to a highly earthquake–prone country.

Energy is dissipated along the sides of the wall by the pressure applied at the four corners of the stone wall. Because the stones of the inner wall surface are roughly stacked in order to absorb and disperse energy, the “ishigaki” wall would easily collapse without the “yagura”, or turrets, on top.

Japanese warfare relied mainly on field battles, so “Oshiro” didn’t expect to come under fire. While “Oshiro” could find itself under a temporary besiegement, defensive architecture was never fully developed. Unlike Japan, “Oshiro” in the West were built with the assumption that they would come under siege. Therefore, giant walls and towers were constructed to withstand heavy fire such a cannon attacks.

There are also differences between castle towns surrounding “Oshiro” in Japan and those in other countries. For example, whether or not there was a wall around the castle town. Overseas, wars often occurred between different races of people and once invaded they risked being plundered and massacred.

But in Japan, Samurai fought Samurai in a battle for supremacy over the country and in general, people living in castle towns were not involved, thus no walls were constructed. Instead, towns were designed to confuse the enemy. The “Oshiro” remaining today are highly popular tourist attractions.

You may have been wondering, like me, whether there are any old castles in Japan that have been redeveloped into a hotel, like those you can see overseas. It would be really great not just to visit, but to try living in one. Japan also has something like that!

It's called “Yanagawa Tachibana-Tei Ohana” in Fukuoka prefecture. Its history stretches back 400 years. What was once the residence of the Tachibana Family, the feudal lord of Yanagawa clan, is now being used as an accommodation facility. The “Shoto-En” gardens have been designated as a National Site of Scenic Beauty. Other national treasures and important cultural properties are available for viewing even if you're not a hotel guest.

“Oshiro” - full of history and romance.

Enjoy your visit by trying to imagine how you would carry out an attack and feel just like a feudal lord as you make your climb up to the top of the keep! And if you take a walk around an “Oshiro” you may find yourself walking in the steps of a samurai...

It is my opinion and summary. Please acknowledge that there are various opinions.