The Japanese League was created in 2132 as the New Nippon System's entry into Republican Baseball.
Originally, Republican Baseball considered adding the Japanese League's teams to the divisions within the existing divisions, but with New Chicago wanting to field teams as well and the time it would take to travel back and forth between the star systems, it was deemed better to form a separate league for the two worlds of the New Nippon System so that travel times would remain relatively short. Then the winner of the league penant would play the winner of the then Galileo-Athena League for the championship.
For a little while, Kaesong fielded teams within the Japanese League until the creation of the Cross Republic League in 2152. However, all three current divisions are now made up exclusively of teams from Yamanashi and Kanagawa.
Current Teams
- Kanagawa Division
- New Seto Sea Dragons (2130)
- (New Seto) Kanagawa Giants (2130)
- New Chiryu Marines (2130)
- New Chiryu Tuna (2130)
- Yamanashi Division
- New Onojo Sea Lions (2130)
- New Onojo Samurai (2130)
- New Souma Warriors (2130)
- New Souma Flyers (2130)
- Intra-Nippon Division
- Mobara Tigers (2130)
- Anjo Gnats (2130)
- Katsuyama Japanese (2130)
- New Souma Fighters (2130)
