thasos revolted in order to be free of
Thasian rebellion The Thasian rebellion was an incident in 465 BC, in which Thasos rebelled against Athenian control, seeking to renounce its membership in the Delian League. The rebellion was prompted by a conflict between Athens and Thasos over control of silver deposits on the Thracian mainland, which Thasos had traditionally mined.
Athenian democracy Increasingly, responsibility was shifted from the assembly to the courts, with laws being made by jurors and all assembly decisions becoming reviewable by courts. That is to say, the mass meeting of all citizens lost some ground to gatherings of a thousand or so which were under oath, and with more time to focus on just one matter (though never more than a day). One downside was that the new democracy was less capable of rapid response.