The word castle conjures up images of Europe, but it was the Japanese who adapted it to the changing times and blended strength with beauty and grace. Castles are also attributed to William the Conqueror whose invasion of England in 1066 triggered the stupendous erection of these structures. Six hundred years later, they began losing their value as a defense structure with the advent of potent gunpowder and artillery. 

In Japan, the castle assumed its original form during the Nara Period of 545-794 AD. Then these structures made their transition from wood and stone fortifications to those having forts and moats as feudal warlords became increasingly belligerent. This was the underlying logic behind castle building – adapting to the requirements of the warlords and the changing times. The castle was primarily built for defense purposes. When under attack, the warlords and their men retreated into the towers, which also doubled as granaries and armories. The towers began to epitomize power and wealth – the bigger the tower, the mightier and wealthier the warlord. Soon enough, the castle became synonymous with both. 

At one time, there were an awesome 30,000 to 40,000 castles in Japan built between 1333 and 1572. Hundreds of the mountaintop castles were constructed in the Sengoku Period, also known as the Warring States Period which witnessed the bloody civil wars. Though the castles were small, they had huge watch towers. Then the castles came to the plains. The Azuchi Castle was built in 1579 by Oda Nobunaga who later embarked upon the unification of larger sections of Japan. This process automatically rendered a majority of the medieval structures irrelevant which soon fell into disuse.

Azuchi changed the tenets of castle building in the country and reoriented the definition to have the structure demonstrate not just protection but also the builder’s status. The presence of a vantage point determined if the area was worthy of castle building. With this, the structures became more complex. The very planning became a detailed and time-consuming process. They had to be protective, at the same time artistic and grand to demonstrate the owner’s power and social standing. These aspects were enhanced by the growing influence of the Samurai clans. The Japanese were exposed to firearms in the mid-1500s and this further changed the castle from being a secure structure to one having military advantages.  

Gradually, the castle began to encompass every aspect of daily life. Apart from its military significance, the castles became nerve centers of governments and army headquarters. These also accommodated typical palace politics of alliances and one-upmanship. The castles had huge grounds that evolved into entire townships, bringing in different people in areas of trade, crafts, agriculture and fine arts. The emergence of the castle township directly determined the prosperity of the area. 

Peace became palpable during the Edo Period, 1603-1867 AD and Tokugawa Ieyasu unified all of Japan under one government. He built the Edo castle in Tokyo whose fortress was made of cedar. The roofs were made with copper to prevent fires that could be set off by the enemies’ flaming arrowheads. Soon after, the “Ikkoku Ichijoo” law was enacted that made it mandatory for every province to have just one castle. After this, several castles were razed. The 250-year reign of peace began the decline of the castles’ importance – first from a military standpoint and later, the social standpoint. 

In 1873, the Meiji government passed the Castle Abolishment Law to mark the end of all those structures that served as a reminder of the feudal period. Within two years, at least 100 of the 170 Edo Period castles were destroyed. The ripped-up parts of the grand castles were sold as firewood and the stones used for dam and railway constructions. The rest were lost to earthquakes and fires. Whatever was left collapsed to World War II bombings. Today, a dozen of the original castles with their characteristic huge towers remain, though much of the adjoining lands and sprawling gardens have been lost with time.