When you visit one of the larger cities in Japan,
you will generally find a central park area. More often than not, the park
is where the local castle once stood. The only hint that a castle existed
there may be a set of stone steps or a large wall of fitted stones. However,
scattered throughout the country are existant castles that have stood the
test of time, wars and political changes. Old castles in Japan are unique
in all the world. Their elegant architecture seems to belie their original
function as a fortification. They were originally built for the protection
and defense of the regional daimyo. But in later years they represented
the central authority and power of the daimyo. Castles evolved as the political
climate changed. As peacetime prevailed, castles became the symbol of the
administrative center of the community and less of a fortress.
Prior to the Sengoku Jidai, the Age of Civil War (1467-1568), the daimyo would typically have a manor house where he and his family would reside during peacetime. When attacked the family and clan would flee to a protective fortress. Generally these would be on a mountain or some terrain which would provide natural defense. These fortresses were little more than wood palisades or stockades and they were built as temporary structures. But during the Sengoku Jidai, more permanent structures were built, similar to their regular manor house residences but on a much grander scale. Because of this, watchtowers were an essential feature added to the building compound. Castles became the primary residence instead of a secondary one.
Castle architecture evolved from these forms. Typically, in early castle construction, topography was the determinent factor as to where a castle was located. Mountain tops and peninsulas were the primary sites. Castles are usually categorized by the terrain on which they are built. Yamajiro are mountain castles, built on mountain tops for the natural defenses. Buildings in the yamajiro complexes are typically only two stories in height, since the natural height of the mountain affords the lookouts an unobstructed view. Hirayamajiro castles were built on plateaus or the leveled tops of hills. These were usually the most difficult to build since some of the outer building had to be built on terraces. Hirajiro are castles on plains or flat lands. Hirajiro became more prevalent as the necessity to build in more inaccessible areas decreased. Hirajiro were the easiest to build since they did not have to contend with uneven terrain. Because hirajiro did not have natural defenses, unless they were built next to water or swamps, other defensive measures had to be developed. These defenses usually took the form of high stone walls surrounded by a series of moats, both dry and water. The introduction of firearms and eventually cannon changed castle construction. Although the castle construction was still primarily wooden structures, the outer walls were covered with layers of plaster called nurigomezukuri to thicken the walls and make the castles more fire resistant.
In the 1560's, Oda Nobunaga became the foremost daimyo in Japan. Over a short period of time he expanded his influence throughout central Japan and into Kyoto where he ended the Ashikaga shogunate rule. Between 1576 and 1579, Oda Nobunanga had Azuchi Castle built. It became the prototype for all subsequent major castle developments. It was a magnificent and enormous structure. It featured a central donjon, tenshu, which was the first of its kind. The castle towered over the landscape. Nobunaga employed the finest craftsmen and artists in the land to build and decorate the castle. The major feature was the tenshu which was more than seven stories tall, overlooking Lake Biwa and the surrounding territory. Architects were knowledgable in large scale building through temple construction. But Azuchi castle was different because it was the first time such a large multi-storied structure had been attempted. The fact that they could design and accomplish such a feat in four years bears testament to the power and force of Nobunaga's rule. Kano Eitoku, the greatest painter of that age is said to have decorated the interior of the castle. Unfortunately Azuchi Castle was destroyed in 1582 at the time of Nobunaga's assassination in Kyoto. All that remains are the stone steps seen in the picture above.
Three of the most famous castles are located in
centers of Tokyo, Kyoto, and Osaka. In Tokyo, the Imperial Palace compound
is found within the innermost grounds of the Edo Castle of the Tokugawa.
It was built in the early 1590's and rebuilt a number a times as it expanded.
The inner moat and stone walls, about 4 miles in total length, are what
we see today as the outer boundaries of the Imperial Palace. Edo Castle,
also called the Chiyodajo, was the largest castle in the world at its prime.
Its outer defense perimeter was 10 miles in length at that time. A series
of disasterous fires destroyed many of the main building including the central
donjon in the 1860's.
Kyoto had a number of castles in and around its center. One of the first built within Kyoto was for Hideysohi Toyotomi. It was his pleasure palace called the Jurakudai. It was said that the lavishly decorated castle built solely for receiving visits from the emporer Goyozei. Jurakudai was built in 1592 and was either demolished by fire or dismantled in 1595. Hideyoshi had already moved his residence to Osaka castle which was built in the 1590's. It was the largest castle complex of its time with five donjons, the tallest of which was said to be nine stories tall. The castle stood until 1615 when it was burned to the ground in final defeat of the remaining Toyotomi loyalists by the Tokugawa There is presently a castle on the old grounds in Osaka but it is a modern smaller scale rebuild. The picture on the left is the inner moat, stone wall, and the rebuilt donjon.
To demonstrate his supremacy ,Tokugawa Ieyasu completed
Nijo Castle in the middle of Kyoto in 1603. Not only was it his residence
when he traveled to Kyoto, it was also a reminder to the Imperial court
of who really ran things
. Nijo was a castle built
for peacetime use. Its surrounding moat and smaller scale stone walls was
symbolic of the shogunate's power. Its original keep was brought from the
nearby Fushimi castle (another castle built by Hideyoshi) in 1624-1626.
Its donjon was destroyed by fire in 1750. The main remaining building is
the Ninomaru Palace, a secondary building compound, and is designated as
a National Treasure. Within the Ninomaru Palace are beautiful paintings
by the Kano school and the famous Nightingale floor, which squeaks when
you walk across it, warning others that someone is approaching. The picture
to the right is the corner turret and moat of Nijo castle.
The best existing example of castle construction
in its prime is Himeji Castle in Hyogo Pref
ecture, formerly
Harima Province. It was built by Ikeda Terumasa in 1609 at the ultimate
time of castle construction. Terumasa, the lord of Harima, was a major vassel
of the Tokugawa (he was Tokugawa Ieyasu's son-in-law). This castle, built
in the same grand design as its predecessors, indirectly represented the
power and authority of the Tokugawa to the western daiymyo who were predominantly
on the opposing side at the battle of Sekigahara (1600) and later the Osaka
Castle campaign. It was built to keep the western daimyo in check. But its
construction was unsurpassed in its day. The walls were made of many layers
of thick white fireproof clay. Because of this and its sweeping rooflines
it is also called the Shirasagi-jiro, White Heron Castle. Supposedly
it looks like a white heron in flight. In 1956 it was closed for eight years
while significant restoration was accomplished by skilled craftsmen.
Himeji is an example of a hirayama-shiro.
It is built on an approximate 135 foot rise called Himeyama. The central
tower or donjon, tenshu, rises another 96 feet. It is a five story, seven
floor structure. The bottom floor is built within the stone walls, this
"basement" floor would not be visible from the outside. Multi-floor
construction is supported by two large central columns that run the entire
height from the foundation to the top roof. Multi-story contruction borrowed
its principals from pagoda architecture, but this scale was much grander.
In addition to the main donjon, there were three other smaller donjons that
were all connected by roofed corridors called watariyagura. These
complexes composed the main central compound. Several other compounds extended
from the main complex and were surrounded by walls and moats. Himeji has
a very complex system of gates, twenty-one in all and corridors leading
to them. These were used to confuse and slow up the enemy and provide opportuities
for defense by the castle inhabitants. The labrynth of gates and halls can
wind around to lead the enemy into dead ends just when they think they are
getting closer to the main donjon. While going from gate to gate, the attackers
would have been subjected to attacks by the defenders using loopholes through
the walls to shoot arrows or guns.
One of the oldest existing hirajiro is the Matsumoto
castle located in Matsumoto city in Nagano 
Prefecture. The
Matsumoto castle was built in 1596. It is only one of two existing castles
that predate 1600. Its main tenshu is six stories high. It contrasts with
Himeji in that its wainscoating is adorned in black lacquer with red lacquered
railings. Matsumoto is called the Crow Castle because of this black lacquer
treatment. It is a fine example of complex connected donjons, in Japanese
called fukugo renketsushiki tenshu. The main donjon, second donjon,
turret and a moon viewing pavillion are all architecturely interconnected.
Himeji falls into the multiple donjon construction style called renritsushiki
tenshu. Other donjon styles are stand alone main donjons, dokuritsushiki
tenshu; and main donjon with other structures connected by corridors,
renketsushiki tenshu; and complex donjons fukugoshiki tenshu.
This writer has had an opportunity to climb to the top floor of Matsumoto
Castle. One of the defensive features found in the interior are steep narrow
steps which makes an enemy's intrusion to higher floors very difficult.
When viewing a castle
up close, the first impressive features are the massive stone wall foundations,
ishigaki. Generally, it is the stone walls that remain when the towers
of castles have long been destroyed. It is usually these walls we see in
the central parks. These walls may first appear to just be stones piled
on each other. But on further inspection, a great deal of care was taken
in the placement of each stone, and the fact that they remain intact after
centuries is a testament to their engineering. There are many styles of
stone walls, from straight, to slightly curved, to very curved. The specific
type depends on the tenshu they have to support and the substratum that
is there to support the wall. Of course, the amount of labor needed to construct
such walls was monumental and the manpower used was often forced. The sheer
magnitude of these walls is very impressive to us as casual observers; imagine
how impressive it was for any attacking army to try to scale such edifices.
Anchoring each corner were huge cut corner stones. The stone walls pictured
right are those of the Osaka Castle. Typically, turrets were strategically
placed on these walls to serve as lookout towers. Although smaller in scale,
they usually reflected the building style of the main donjon.
Some of the most interesting features of castles are those that are specifically related to the defense of the castle. As mentioned before, the use of moats was the first line of defense. These moats could be either dry or filled with water, with water moats being most employed. One of the negotiation points the Tokugawa and the Toyotomi had between the Winter and Summer Campaigns of 1615 was the filling in the moats at Osaka Castle. Typically, there would be outer moats protecting the outer perimeter and then an inner moat protecting the central compound. Essential to larger castle complexes are the series of mazes previously mentioned. These mazes are designed into the plans to confuse the enemy who may have breached the outer walls. Many of the mazes double back and have dead ends. As the enemy negotiates these corridors in confusion, they are susceptible to attack. In addition, the thick walls on one side of the corridor would have loopholes constructed into them. These loopholes, teppozama, were hourglass-shaped openings that allowed the castle defenders to fire into the enemy while making their way to the next gate. The openings were thinly plastered over so the enemy would only see a solid wall. The defenders would break through the thin plaster and then fire at the enemy. A grouping of such teppozama is shown in the picture of the wall at Himeji Castle.
Castle gates were always considered
to be the most vunerable points in castle defense.The main gate had to be
both an imposing structure and a deterrent to the enemies advancement. During
the height of castle building , new defense feature was added to gate architecture.
It is called a masugata, after the shape of a masu, a square
wooden rice measuring box. The masugata was a square area inside the gate,
which had a second gate at a right angle to the front gate. It was designed
to slow the enemy down by creating a bottleneck which provided an opportunity
for attack.
Another feature built out from the castle wall above the ishigaki is the ishiotoshi, the stone drop (see above picture). From these structures rocks and other projectiles could be rained on potential scalers of the sone walls. These stone drops also have arrow and gun ports to fire at the enemy from their height advantage.
Castle defense designs became so sophistocated that they became virtually impregnable to direct attacks. Often a strategy of starving out the inhabitants, or poisoning the water supply was used to make the castle capitulate to surrender. In one instance, an attacking army diverted a river to flood the surrounding land in an effort to starve out the castle. Often castles fell to fire from within by having spies infiltrate the castle. It was mainly the long period of peace that led to the reduction of castles. Shortly after the start of the Meiji Period (1868-1912) there were forty donjons in existence. Many were dismantled during that period and the bombing destruction of World War II reduced the numbers further. There are about twelve existing donjons that have survived. There are also several castles that have been reproduced (Osaka, Odawara, Nagoya, Fushimi) in modern times and are used as museums or tourist attractions. The exiting old castles' graceful lines harken us back to the age when samurai ruled Japan.