In 470 B.C., he sailed to an island named Scyrus, in which dwelt a race of pirates, who had for many years fallen upon and captured the merchant vessels of Greece. The island of Scyrus lay between Athens and Thrace.
The Greek traders were pleased when Cimon banished the pirates, as he was soon able to do. A number of Athenians were sent to settle in Scyrus, which from that time belonged to Attica.
Now there was a legend which said that in this island there was a grave where lay the bones of Theseus, one of the old heroes of Hellas.
It may be that Cimon ordered his men to search for the spot where the hero was said to be buried; in any case a grave was found in which lay the body of a giant warrior. No one doubted that this was the body of Theseus, and, as the oracle had commanded, the bones were brought to Athens and placed in a temple which was henceforth called Theseum. The Athenians were loud in the praise of Cimon because he had obeyed the commands of the oracle, and had brought the bones of the hero to Attica.
Four years later Cimon gained two great victories over the Persians, by which those Greek cities which had been left under the yoke of the great king were set free. They then hastened to join the Delian League.
Cimon was now at the height of his power, but his friendship with Sparta, on which the Athenians had always looked with dislike, soon led to his downfall.
In 464 B.C. there was an earthquake in Peloponnesus. Chasms yawned in the valleys, landslips changed the face of the mountains. The loss of life in Sparta itself was terrible, while both houses and temples were destroyed. The Helots, who were always ready to revolt, did so now that their masters were overwhelmed by this great calamity.
Cimon begged the Athenians to forget their old grudge against the Spartans and to send to her help, remembering only how they had shared in the glory of the Persian war.
‘Do not let Greece be lamed of one foot,’ he urged, ‘and Athens herself be left to draw without her yoke-fellow.’
An Athenian, named Pericles, who was now one of the chief citizens, did all he could to make the people refuse to send help to Sparta, but Cimon’s entreaties were successful. He was himself sent at the head of the Athenian troops to help the Spartans to subdue the Helots.