The Goryokaku Fortress

The Goryōkaku (五稜郭 five-point enclosure/fortification) was designed in 1855 by Takeda Ayasaburō, a rangaku (Dutch studies) scholar under Bakufu orders. Hakodate, a small port city in southern Ezo (Hokkaido), was strategically selected. Although not part of Japan, the island of Ezo was to remain under the control of the Matsumae clan following a shogunal edict in 1604 (Black seal letter from Tokugawa Ieyasu to Matsumae Yoshihiro, first daimyō of Matsumae Domain, granting the Domain exclusivity as intermediaries in trade with the people of Ezo (Hokkaido Museum) see picture above). Following the Perry expedition of 1853 and the end of the seclusion period, the threat of Russia was becoming more tangible. The 1855 Treaty of Shimoda that opened the port of Hakodate to commerce made their interest in Ezo clear. The Bakufu, bereft of a navy, built this fortress with the purpose of protecting the Tsuruga straits from a potential Russian invasion.

Takeda was inspired by the designs of Sébastien Le Prestre, Marquis of Vauban (1633-1707), a French military engineer known for his star-shaped forteress The construction of the main structure of the Goryōkaku was completed in 1864. The surface of the fort measures 125,000m2.

In addition to the main moat, 4-meter-wide dry moats were built on both sides of the three entrances. The moat is approximately 30 meters wide at its widest point, approximately 4 to 5 meters deep, and has a circumference of approximately 1.8 kilometres.

The Goryōkaku was only used then as an administrative base for margistrates, but at some point during the civil war of Boshin in 1868, Tokugawa loyalists headed north and conquered it. It was then used as the headquarters of the Republic of Ezo, founded there in December of that same year!

Today, you can visit most of the remaining structure and the park around it.

More on this: 

• Oleg Benesch and Ran Zwigenberg, Japan’s Castles: Citadels of Modernity in War and Peace (Cambridge: Cambridge University Press, 2019). ISBN 978110868057