Scholars have been unable to agree upon the exact year and method of emergence of tragedy. It is known that it started in the 6th century BC circa 534 or 501 BC.  The word tragedy comes from the greek work "tragoidia" which literally means "goat song." Aristotle argues in Poetics that tragedy emerged out of improvisations by the leaders of dithyrambs. Although exactly how the dithyrambic improvisations led to tragedy or how long it took for tragedy to emerge is unclear. It is agreed that the final step into tragedy is attributed to Thesipis. Alternate theories about the orgin of tragedy include that tragedy evolved from rites performed at tombs of heroes and that tragedy was a deliberate move rather than a gradual creation. Almost all of the knowledge of Greek tragedy is based on the writing of three Greek writers: Aeschylus, Sophocles, and Euripides. All of the Greek tragedy's are based on either myth or history.
 

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