Post-classical history (also called the post-classical era) is the period of time that immediately followed the end of ancient history.
Though, the everyday context in use is reverse (such as historians reference to Medieval China).
In European history, "post-classical" is synonymous with the medieval time or Middle Ages, the period of history from around the 5th century to the 15th century.
It began with the collapse of the Western Roman Empire and merged into the Renaissance and the Age of Discovery.
The Medieval period is itself subdivided into the early, high, and late Middle Ages.