Peisistratos died in 527 or 528 BC. His eldest son, Hippias, succeeded him as tyrant of Athens. Hippias and his brother, Hipparchus, ruled the city much as their father had. After a successful murder plot against Hipparchus conceived by Harmodius and Aristogeiton, Hippias became paranoid and oppressive. This change caused the people of Athens to hold Hippias in much lower regard. The Alcmaeonid family helped depose the tyranny by bribing the Delphic oracle to tell the Spartans to liberate Athens, which they did in 508 BC. The Peisistratids were not executed, but rather were mostly forced into exile. The surviving Peisistratid ruler, Hippias, went on to aid the Persians in their attack on Marathon (490 BC), acting as a guide.