There was a documentary on BBC 4 last night at 9pm called Ancient Greece: The Greatest Show on Earth. In it, classicist Dr Michael Scott looked at Greek drama. Although the main focus was on the role drama played in democracy in Athens, there was also a great deal about its importance as a religious ceremony in the honour of Dionysus, the god of theatre as well as the god of wine.
I found the programme very interesting and you can still see it on BBC iPlayer: http://www.bbc.co.uk/i/b039fpnk/
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