In the second half of the 6th century BC, Athens fell under the tyranny of Peisistratos followed by his sons Hippias and Hipparchos. However, in 510 BC, at the instigation of the Athenian aristocrat Cleisthenes, the Spartan king Cleomenes I helped the Athenians overthrow the tyranny. Sparta and Athens promptly turned on each other, at which point Cleomenes I installed Isagoras as a pro-Spartan archon. Eager to secure Athens' independence from Spartan control, Cleisthenes proposed a political revolution: that all citizens share power, regardless of status, making Athens a "democracy". The democratic enthusiasm of the Athenians swept out Isagoras and threw back the Spartan-led invasion to restore him. The advent of democracy cured many of the social ills of Athens and ushered in the Golden Age.