http://agathe.gr/democracy/theater.html
Theater Western drama was an Athenian invention which developed late in the 6th century B.C. out of the festivals celebrated in honor of the god Dionysos. Originally held in the Agora, the plays were soon ... In addition to several dozen surviving tragedies by Aeschylos, Sophokles, and Euripides and comedies by Aristophanes and Menander, our knowledge of Athenian theater is enhanced by the dozens of small terracotta figurines and masks depicting the numerous stock characters who appeared in the plays. ... The statuettes represented add new types to those known from the literary sources and enrich our picture of the Athenian theater during the 4th century. ... The mask is characterized by the slightly twisted, trumpet-shaped mouth typical of slave masks. The hair has been combed back from the forehead, and a short beard frames the mouth.