Daikoukai Jidai Gaiden is a Strategy game, developed and published by Koei, which was released in Japan in 1997.

Uncharted Waters is a popular Japanese video game series produced by Koei as part of its rekoeition games. In East Asia, the series has a large cult following, but has not received much recognition outside East Asia. The series has been compared to Sid Meier's Pirates! in gameplay and theme. It is a simulation and CRPG series dealing with sailing and trading.

Daikoukai Jidai Gaiden is a side story released in 1997 on PlayStation and Sega Saturn after New Horizons, the game uses the same engine and focuses on the story of two characters instead, further expounding upon the loose plot that ties the series together.