a period in history which lasted for roughly a millennium(千年) commonly dated from the fall of the Western Roman Empire in 476 with the attack of Rome to the beginning of the Early Modern Period in the 16th century ❖ a period in history which lasted for roughly a millennium(千年) ❖ commonly dated from the fall of the Western Roman Empire in 476 with the attack of Rome to the beginning of the Early Modern Period in the 16th century