Answer
Dionysus is a god of mystery religious rites. He is not half-man and half-god, but rather a fully divine being who conceals himself in human disguise. Many scholars believe that Dionysus is a syncretism of a local Greek nature deity and a more powerful god from Thrace or Phrygia, such as Sabazios.
There are many parallels between the stories of Dionysus and Jesus. Both were said to have been born from a mortal woman but fathered by a god, to have returned from the dead, and to have transformed water into wine. Dionysus is often represented on a donkey riding in triumph and to his death.

(Correction ... he usually rides a panther ... parallels to Jesus are a little overdrawn. Yes, they exist, but there are parallels also with Orpheus, Mithras, Adonis and other mystery cults ...)

Here you go...Join the Armed forces, get drunk all the time, and kill like a mad man in a war.
The Greeks invented this religion to help with the creation of super warriors. What better way than to worship mayhem and murder in the name of... Dionysus is the god of wine and VIOLENCE. I am sure that plays were written for him. Plays have been written for warlords, tyrants, and even the devil. The real way was the Feast of Dionysius. I am sure there is more to this. I used Dionysius in a modern war short story that I wrote. (Like I said in the first line.)


Significant CORRECTION to the above: Dionysos was notthe god of violence. The above answer has confused him with Ares. Ares was the god of brutal warfare (conceived of as tharsos), while Athena was the goddess of reasoned, strategical warfare (associated with andreia). Dionysos is RARELY, in fact, associated with war or the battlefield ... he's notably absent at Troy, for instance. He was a FERTILITY god ... associated with life (zoe), not death. He was also the god of (divine) madness and could drive people to violence, but almost always in response to something (most often refusal of worship). Like most gods, there are two sides to Dionysos -- the light god and the dark god. The light god brought joy, pleasure, and ecstatic experience, of which wine was symbolic. But the dark side of wine is to turn people violent and erratic, when too much is consumed. As always for the Greeks: "Moderation in all things."

AnswerDionysus is the Greek god of wine and drama. The Greeks wrote and performed plays--both tragedies and comedies--for him. Also, their is a Greek festival, Dionysia, that was done annually for him.


Additional Information:
As with most of the "Great Gods" (main deities), there were a variety of festivals to Dionysos throughout the year, and he was sometimes included as parts of other festivals. (Festivals often had a main deity honored, but also attendant or related deities worshiped as well.) Dionysos was "in charge" of an unusual number of areas, perhaps as a result of syncretization (as mentioned above, although associations with Sabazios are quite late). He was a god of growth, particularly grove and vineyards. (Demeter was the goddess of grain/fields.) In this respect, he became associated with wine and wine-making, his other most common "face." Fertility is all wrapped up in that too. In addition, he was the "god always coming" -- the god of the fringes (of the Greek Oikoumene, and of human experience). He brought divine madness, via wine, but not always. Dance could also lead to ecstacy. This association with the fringes may be why the later association with theatre (which removes us from our "normal" activity for a while), although that was also because theatre appears to be an outgrowth of the spring Dionysias. and the choral hymns sung for him.

First with have the early spring Anthesteria which celebrated the opening of the new wine and was the celebration of the vine. (Dionysos, remember, is called Lord of the Vine, as well as the Ivy Lord.) As there was a Sacred Marriage as part of this, is was almost certainly related to the Babylonian New Year's Festival, albeit distantly. Dionysos is "married" to Ariadne. (In reality, particular officials chosen by lot called the "king" and "queen" [basileus and basilea] -- a husband and his wife -- were stand-ins for the royal pair and consummated the marriage in a special ceremony.)

The (late) spring Dionysia was probably the most popular/best known of his cults. This was celebrated by feasting, choral performances, and later by some theatrical performances, and by parades (pompe) ... which typically included great big floats of male phaluses. (Imagine getting one of THOSE by the judges of the Rose Bowl Parade!). Remember ... fertility god. ;)

(There was also a rural or Lesser Dionysia in December, where "repeat performances" of certain popular dramas were given.)

Last, there was the Lenaia, a winter festival. This is the festival when the Tragedies were typically presented (not the Greater Dionysia! A common misconception!). Again, it was a wine festival, when the wine had finished fermenting and was supposedly "born." According to myth, Dionysos was born in winter.

These are the main PUBLIC festivals of Dionysos. They're quite different from the Mystery Rites. Unfortunately, the ancients kept their mysteries a mystery, so we don't know a lot about it beyond literary reference like that in The Bacchai (a tragedy by Euripides). But as with any such reference, one has to be careful about taking things too literally.