In the late fifth and fourth centuries BC there were three annual festivals in Athens at which major choral competitions were held. At the Thargelia, held in Thargelion, there were contests for dithyrambic choruses of men and boys. The first formal steps to arrange these contests were taken in the previous summer, when a khoregos was appointed for each of the required number of choruses. This procedure, as far as the Dionysia and the Thargelia are concerned, is outlined in the Athenaion Politeia attributed to Aristotle, in an account of the actions taken by the arkhon upon entering office at midsummer. Once the chorus had been recruited, rehearsals went on regularly until the time of the festival, and in this connection we know of another law: a law giving choristers exemption from military service. There was also a law or laws which forbade certain persons to take part in choral performances: disfranchised citizens and aliens.