Mainland Japan
The term's literal Japanese meaning might best be translated as "inner Japan" or "inner lands". The term "mainland" is somewhat inaccurate since it usually refers to all or part of a continental landmass, rather than islands.
"Mainland Japan" was an official term in the pre-war period, distinguishing Japan proper from its colonies in the Far East (which at that time included parts of mainland Asia). After the end of World War II its usage became less common and lost its previous legal significance.
Historical usage
In the Japanese Empire of the pre-war period, naichi referred to the mainland of the empire. The other territories of the empire was called gaichi (外地, lit. "outer lands").
The Meiji Constitution's Article 1 of the Common Law (共通法) enumerates the territories with legal jurisdictions namely:
Naichi
Naichi (内地, lit. "inner lands") referred to the territories under direct control of the government. They consisted of the following:
- Karafuto (since 1943)
- Chishima Islands (since 1875)
- Hokkaidō
- Honshū
- Shikoku
- Kyūshū
- Izu Islands
- Ryukyu Islands (since 1879)
- Nanpō Islands (since 1891)
- Minor outlying islands around them
Gaichi
These territories were called gaichi (外地, lit. "outer lands"). They were part of the Empire of Japan, but not under direct control by the central government.
- Hokkaido (until 1947)
- Ryukyu Islands (until 1879)
- Taiwan
- Shinnan Islands (since 1938)
- Seisa Islands (since 1938)
- Karafuto (until 1943)
- Chōsen
- Kwantung Province
- South Manchuria Railway Zone
- South Seas Mandate
- Kiautschou Bay Leased Territory
- Tianjin
- Hankou
- Chongqing
- Suzhou
- Hangzhou
- Shashi
Although it has never been abolished, the Common Law lost effect from enforcement after Japan lost all the former colonies, or gaichi as a result of World War II.
Modern usage
The residents of Hokkaidō and Okinawa occasionally use naichi to refer to the "mainland", excluding these areas. The colloquial usage is officially "incorrect", as both areas are legally within naichi. In Hokkaidō, the official term that refers to Japan except Hokkaidō is dōgai (lit. outside of Hokkaidō). With dōgai becoming common even in colloquial use, naichi ceased to be used.
The term "main islands" (本島 hontō) is used for Hokkaido, Honshu, Kyushu, Shikoku and Okinawa. The other estimated 6,847 smaller islands are called 'remote islands' (離島 ritō).