The Principality of Achaea is one of the three vassal states of the Latin Empire, which replaces the Byzantine Empire after the capture of Constantinople during the Fourth Crusade.

It becomes a vassal of the Kingdom of Thessalonica, along with the Duchy of Athens, until Thessalonica is captured by Theodore, the despot of Epirus, in 1224.

After this, Achaea becomes for a while the dominant power in Greece, and in the mid-13th century the court at Andravida is considered to be the best representation of chivalry by western Europeans.