Ezo

Ezo is a historical term used in Japan to refer to the lands of the northern frontier, especially the island of Hokkaido and its vicinity. The name derives from the Chinese characters 蝦夷 (ezo), used in classical Japanese to designate various northern peoples, later generalized to the land they inhabited. In Japan, the area was known as Ezochi (蝦夷地) and its inhabitants were referred to as Ezo or Emishi in different periods.

During the Heian period, the term encompassed several groups living north of the Yamato state, and it was used in official records and literature. By the Edo period, Ezochi referred to the northern territories administered by the Matsumae clan, and the region remained distinct from Honshu.

In 1869, as part of the Meiji Restoration, the government established the Hokkaido Development Commission and renamed the territory Hokkaido. A brief attempt to form an autonomous Ezo Republic in 1869–1870, centered in Hakodate under Enomoto Takeaki, ended with the imperial government’s victory and the incorporation of Ezo into Hokkaido Prefecture. The term Ezo is now primarily historical and is encountered in academic writing, historical fiction, and discussions of early Meiji era northern policy.

In modern usage, Ezo often appears in discussions of Hokkaido's history or in cultural references that evoke the northern frontier, including botany or zoology where 'Ezo' prefixes indicate the northern Japanese region’s origin.