In 499 BC several Greek cities in Asia Minor rebelled against Persian rule. To help their fellow Greeks, a few city-states in mainland Greece sent soldiers to join the fight against the Persians.

The Persians put down the revolt, but Darius was still angry with the Greeks. Although the cities that had rebelled were in Asia, Darius was enraged that other Greeks had given them aid. He swore to get revenge on the Greeks. This was convenient since Darius wanted the Persian Empire to grow. In the east, he conquered the entire Indus Valley and could go no farther. The only way he could try to expand the empire was westward into Europe and Greece was the entryway to Europe.

The Battle of Marathon

Nine years after the Greek cities rebelled, Darius invaded Greece. He and his army sailed to the plains of Marathon near Athens. This invasion began a series of wars between Persia and Greece that historians call the Persian Wars.

The Athenian army had only about 11,000 soldiers, while the Persians had about 15,000. However, the Greeks won the battle because they had better weapons and clever leaders. The Persians return home defeated and Darius gave up him dream of expanding his empire into Greece. 

According to legend, a messenger ran from Marathon to Athens-a distance of just over 26 miles-to bring news of the great victory. After crying out "Rejoice! We conquer!" the exhausted runner fell to the ground and died. Today, we recreate this in events where runners run a 26-mile race called marathons. 

The Second Invasion of Greece

Ten years after the Battle of Marathon, Darius's son Xerxes I (ZUHRK-seez) tried to conquer Greece again. In 480 BC the Persian army set out for Greece. This time they were joined by the Persian navy.

The Greeks prepared to defend their homeland. This time Sparta, a powerful city-state in southern Greece, joined with Athens. The Spartans had the strongest army in Greece, so they went to fight the Persian army. Meanwhile, the Athenians sent their powerful navy to attack the Persian navy. To slow the Persian army, the Spartans sent about 1,400 soldiers to Thermopylae (thuhr-MAH-puh-lee), a narrow mountain pass. The Persians had to cross through this pass to attack Greek cities. For three days, the small Greek force held off the Persian army. Then the Persians asked a traitorous Greek soldier to lead them through another pass. A large Persian force attacked the Spartans from behind. Surrounded, the brave Spartans and their allies fought to their deaths. After winning the battle, the Persians swept into Athens, attacking and burning the city.

Although the Persians won the battle in the pass, the Greeks quickly regained the upper hand. A few days after Athens was burned, the Athenians defeated the Persian navy through a clever plan. They led the larger Persian navy into the narrow straits of Salamis (SAH-luh-muhs). The Persians had so many ships that they couldn't steer well in the narrow strait. As a result, the smaller Athenian boats easily sank many Persian ships. Those ships that were not destroyed soon returned home. Soon after the Battle of Salamis, an army of soldiers from all over Greece beat the Persians at Plataea (pluh-TEE-uh). This battle ended the Persian Wars. Defeated, the Persians left Greece.

For the Persians, this defeat was humiliating, but it was not a major blow. Their empire remained strong for more than a century after the war. For the Greeks, though, the defeat of the Persians was a triumph. They had saved their homeland.