Solon (594 BC), Cleisthenes (508/7 BC), and Ephialtes (462 BC) all contributed to the development of Athenian democracy. Historians differ on which of them was responsible for which institution, and which of them most represented a truly democratic movement. It is most usual to date Athenian democracy from Cleisthenes, since Solon's constitution fell and was replaced by the tyranny of Peisistratus, whereas Ephialtes revised Cleisthenes' constitution relatively peacefully. Hipparchus, the brother of the tyrant Hippias, was killed by Harmodius and Aristogeiton, who were subsequently honored by the Athenians for their alleged restoration of Athenian freedom.

Solon (594 BC), Cleisthenes (509 BC), and Ephialtes (462 BC) all contributed to the development of Athenian democracy. Historians differ on which of them was responsible for which institutions, and which of them most represented a truly democratic movement. It is most usual to date Athenian democracy from Cleisthenes, since Solon's constitution fell and was replaced by the tyranny of Peisistratus, whereas Ephialtes revised Cleisthenes' constitution relatively peacefully. Hipparchus, the brother of the tyrant Hippias, was killed by Harmodius and Aristogeiton, who were subsequently honored by the Athenians for their alleged restoration of Athenian freedom.

The greatest and longest-lasting democratic leader was Pericles; after his death, Athenian democracy was twice briefly interrupted by oligarchic revolution towards the end of the Peloponnesian War.

Cite: http://en.wikipedia.org/wiki/Athenian_democracy

Herodotos explains that the Persians landed at Marathon on the direction of Hippias who was one of the sons of Peisistratus, and was tyrant of Athens in the 6th century BC. Hippias succeeded Peisistratus in 527 BC. His brother Hipparchus, who may have ruled jointly with him, was murdered by Harmodius and Aristogeiton (the Tyrannicides) in 514 BC. Hippias executed the Tyrannicides and became a bitter and cruel ruler. The stalemate had lasted through the tenth day after the Persian landing at Marathon, when on the morning of the eleventh day the Athenians went to the attack. Herodotos (VI 112) asserts that the Greeks resorted to a method of warfare never used before: instead of marching towards the enemy, they engaged in a race (dromos) for the entire distance that separated the two armies, not less than 8 stadia (probably artabic stadia of 8 to a Roman mile, or 1500 meters). The Greek line was strong on the wings and weak at the center. This distribution of the forces was to be expected since the wings had to withstand the strong Persian cavalry force; in ancient warfare the function of the cavalry was to protect the wings and to harass the enemy wings. In the absence of the cavalry, the Persian wings were unusually weak. The Persian center broke though the enemy lines, but the Greek wings closed behind the Persians. The Persians had no other recourse except to try to run back to their ships. According to the report, the Athenians killed approximately 6400 Persians at a loss of 192 of their own men, but they did not succeed in getting hold of the Persian ships before they could take off from the beach; only seven ships were captured.