Why was the middle ages period once referred to as the "dark ages"

The Dark Ages is a term often used synonymously with the Middle Ages. It refers to the period of time between the fall of the Roman Empire and the beginning of the Italian Renaissance and the Age of Discovery. ... Debate continues to rage among historians over whether the Middle Ages were, indeed, dark or not.

ayatollah khomeini can best be described as the leader who declared iran to be an islamic republic.

the main objectives of the progressive movement were eliminating problems caused by industrialization, urbanization, immigration, and political corruption.