In European history, the Middle Ages or medieval period lasted from the 5th 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 Middle Ages is the middle period of the three traditional divisions of Western history: Antiquity, Medieval period, and Modern period. The Medieval period is itself subdivided into the Early, the High, and the Late Middle Ages.

Answer this question, if possible (if impossible, reply "unanswerable"): What event marked the beginning of the Middle Ages?
the collapse of the Western Roman Empire