AGAFG 58

Page fiftyeight. Theo and Melito finally leave the Underworld.

The Anthesteria was just partly a festival of the dead. Mainly it was held in the honour of Dionysos. It took place every spring and lasted for three days. People opened the pithoi with wine that had been stored at the previous vintage and adorned their homes with spring flowers. Social order was interrupted during the feast, as the slaves were allowed to participate. It was also believed that the gates of the Underworld stood open and that the dead freely mingled with the living. Therefore special food was made for the dead, that no one else tasted, and I think that all the temples were closed (except for the sanctuary of Dionysos) so the dead shouldn't pollute them.

In other words, it was a festival of both merrymaking and creepyness. I got the idea to let the origin of the festival to be a deal between Hades and Dionysos. Dionysos could have his dead mother back (though in my version Semele isn't exactly his biological mother), if he made sure that one of his festivals also honoured the dead (something that Hades never could have made people to do. But Dionysos is popular. If he tells people to honour the dead, they just do it).