Question: The Canterbury cap is descended from an ancient headcovering originally worn where?
Related documents: [0]  [DOC] The Canterbury cap is a square cloth hat with sharp corners found in the Anglican communion, similar to the Counter-Reformation's biretta, the notable exception being that a Canterbury cap has four ridges, compared to the biretta's three. It is also soft and foldable, "Constructed to fold flat when not in use..." whereas the biretta is rigid. The Canterbury cap is the medieval "birettum," descended from the ancient "pileus" headcovering. It is sometimes called the "catercap." [END] 
[1]  [DOC] The pileus ( – "pilos", also pilleus or pilleum in Latin) was a brimless, felt cap worn in Ancient Greece and surrounding regions, later also introduced in Ancient Rome. The Greek πιλίδιον ("pilidion") and Latin "pilleolus" were smaller versions, similar to a skullcap. [END] 
Answer: 
Ancient Greece
Ancient Greece