Greek theater began in the 6th century BCE in Athens with the performance of tragedy plays at religious festivals. These, in turn, inspired the genre of Greek comedy plays. The two types of Greek drama would be hugely popular and performances spread around the Mediterranean and influenced Hellenistic and Roman theater. Thus the works of such great playwrights as Sophocles and Aristophanes formed the foundation upon which all modern theater is based.
The early tragedies had only one actor who would perform in costume and wear a mask, allowing him to impersonate gods. Later, the actor would often speak to the leader of the chorus, a group of up to 15 actors (all male) who sang and danced but did not speak. This patched up terra cotta mask might be 2,500 years old. Read more about ancient Greek theater masks.