This event was not a mere empty question about a point of honour. It was a real revolution, terminated by a solemn league, of which Athens was to be the head. Aristides took the lead in the matter, for which his proverbial justice and probity eminently qualified him. The league obtained the name of "the Confederacy of Delos," from its being arranged that deputies of the allies belonging to it should meet periodically for deliberation in the temple of Apollo and Artemis (Diana) in that island. Each state was assessed in a certain contribution, either of money or ships, as proposed by the Athenians and ratified by the synod. The assessment was intrusted to Aristides, whose impartiality was universally applauded. Of the details, however, we only know that the first assessment amounted to 460 talents (about 106,000L sterling), that certain officers called Hellenotamiae were appointed by the Athenians to collect and administer the contributions, and that Delos was the treasury.
Such was the origin of the Confederacy of Delos. Soon after its formation Aristides was succeeded in the command of the combined fleet by Cimon, the son of Miltiades.