Why was Athens, Greece important in theatre history?

Western theater and theater criticism began in Athens. It originated from choral performance. In the archaic period, choruses would sing and dance as part of religious festivals, often recounting stories of gods and heroes. Thespis is credited with creating Greek drama by adding a separate role for an actor who engaged in dialogue with the chorus. Aeschylus added a second actor, allowing for more realistic and flexible forms of dialogue. Of the many known dramatic works, those of three great tragic playwrights, Aeschylus, Sophocles, and Euripides, continue to be performed and greatly influenced the development of western tragedy.
The Old Comedy of Aristophanes and satyr plays were equally innovative, serving not just as entertainment but as a form of social critique. They were bawdy and imaginative and also have had a significant influence.
Finally, New Comedy, especially as preserved in the plays in Menander, was the origin of romantic comedy, featuring ordinary people with plots often centering on the trials and tribulations of young lovers leading to happy endings. These plays influenced Roman comedy, and thence much of modern drama.