Why were the Persians a fearsome enemy?

Answer 1

They Conquered Diffrent civilizations, when they conquered civilizations they had enough humane to let them govern themselves.

Answer 2

Theoretically the armies of the Persian Empire at its peak numbered 2 million. However most were low grade local levies. The core force of Persians and Medes were noted fighters, but had problems being unarmoured, having wicker shields which put them at a disadvantage against armoured Greek warriors. Their cavalry was strong, so the Greeks tried to fight the Persians on broken ground. A great part of their strength was golden - they astutely use bribery in preference to battle. Before Xerxes' invasion of Greece in 480 BCE his agents were busily bribing Greek cities, and many cities went over to his side. However the greatest element was the navy, which could threaten amphibious attacks which forced the Greek cities to keep their armies at home protecting their city walls, which left them open to defeat one at a time. The Persians success came not from having the fiercest lot of soldiers, but combining alliances, diplomacy, bribery, strategy, timing and manoeuvre with actual fighting to finalise the other activities. When it came to fighting, after 50 years of warfare against the Greeks, the Persians realised they were losing and gave up their dream of a Pax Persica and left the Greeks to go back to their usual fighting each other, while they (the Persians) concentrated on running its core empire peacefully and competently.

Answer 3

It had a strong system of government - 20 provinces with Persian governors controlled by the king and his council.

Answer 4

The Persian Army was large and well-disciplined. Additionally, it featured war elephants and advanced technology for its time.