Okazaki Castle

Okazaki Castle, located in Okazaki City, Aichi Prefecture, is a historic Japanese castle also known as “Ryūjō” (Dragon Castle). It is most famous as the birthplace of Tokugawa Ieyasu, giving it immense significance in Japanese history. From the Sengoku period to the Edo period, Okazaki Castle witnessed the rise of the Matsudaira clan (later the Tokugawa family), who grew from local lords to the rulers of a unified Japan. During the Edo period, it served as the administrative headquarters of the Okazaki Domain.

Originally, the castle was called “Okaki Castle.” According to the Mikawa Province Topography, the place name “Okazaki” first appeared during the Kyōroku era in 1528; before that, the area was known as “Sugao-go.” The origins of the castle trace back to the mid-15th century, when Niki clan’s deputy governor Saigō Tsuguyori built a residence near the south bank of the Sugao River (present-day Oto River) at Myōdaiji, known as “Hiraiwa Castle.” Later, he constructed a fort on Ryūtōzan Hill, north of the Sugao River, which became the prototype of today’s Okazaki Castle.

In 1524, Matsudaira Kiyoyasu seized the fort through military action and transferred his power base from Anjō to this site, expanding the fortifications. This event laid the foundation for Okazaki Castle to become the stage of the Tokugawa clan’s rise. By the early 17th century, Tokugawa retainer Honda Yasushige and his descendants carried out major renovations, transforming the original hilltop fort into a flatland castle with a tenshu (main keep) and multiple baileys. In 1617, a three-story, three-tiered watchtower-style keep was completed.

At its height, Okazaki Castle was the third largest in the Tōkai region, with a comprehensive structure including the Honmaru (main bailey), Ninomaru, Sannomaru, and multiple outer moats. However, following the Meiji government’s Haijōrei (Castle Abolition Ordinance), the castle was dismantled in 1873, leaving only stone walls and remnants of its baileys.

In 1959, Okazaki City reconstructed the tenshu, restoring its exterior based on historical records. In 2010, the Higashi-sumi Yagura (East Turret) was rebuilt in wood, along with a 45-meter-long section of walls and stone ramparts, faithfully recreating the Edo-period appearance. These reconstructions established Okazaki Castle as both a tourist attraction and an educational site. In 2023, in connection with NHK’s historical drama What Will You Do, Ieyasu?, the exhibitions inside the castle were completely renewed, while the nearby Mikawa Bushi Ieyasu Museum was remodeled into a dedicated Taiga drama pavilion, drawing large numbers of visitors.

Today, Okazaki Castle stands as the centerpiece of Okazaki Castle Park and continues to serve as a landmark for showcasing the history of Tokugawa Ieyasu and the culture of the Mikawa samurai.