Daikoukai Jidai (also known as 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 the region. The series has been compared to Sid Meier's Pirates! in gameplay and theme. It is a simulation and role-playing video game series dealing with sailing and trading.