In the Greek tragedy Antigone by Sophocles, the narration is performed by the Council of Theban Elders, also called the Chorus. Rather than having an outside narrator appear on stage to inform the audience members of things they need to know, Sophocles used an interesting device of having the council of elders, who are always at hand to advice King Creon, perform that function. The Chorus has several functions in the play, in fact. First, it provides the most poetic and artistic passages of the play, reciting choral odes that include elevated commentary on the themes of the play. These include the Ode to Man, Ode to Love, and Ode to Zeus. Second, the Chorus informs the audience of how it should react to the story as it progresses. Initially the Chorus sides with Creon, but as Antigone and Haemon make their arguments and when Tiresias the prophet adds his perspective, the Chorus changes its mind and sides with Antigone.

The third function of the Chorus, as mentioned, is to elucidate actions that occur before the play and off stage. Thus they give the backstory of the two brothers killing each other in battle, and they describe the deaths of Antigone, Haemon, and Euridyce. They provide a summation of the story as well, ensuring that the audience understands the point of the play, namely that:

Wisdom is the supreme part of happiness; and reverence towards the gods must be inviolate. Great words of prideful men are ever punished with great blows, and, in old age, teach the chastened to be wise.

Antigone is a Greek play, and the Chorus is the narrator.

The Chorus in a Greek play provides the narration.  Unlike modern plays, the Chorus was actually a big part of the telling of the story.  The Chorus would explain things and describe things that were not taking place on the stage.

For example, Antigone and Ismene discuss their situation, but the chorus steps in and gives a detailed and very colorful explanation, including the details of the battle that left their brothers dead.

He fell in an arc to the hard ground,
torch in hand, the one who with raging onslaught
furiously was breathing
with the rush of the most hateful winds.(135)
But, those things went otherwise,
and great Ares sent them to
various fates, smiting them,
our chariot's strongest horse.

In many Greek plays, the Chorus provides an important role by narrating and commenting on the action of the story.  Things that can’t come across by dialogue make more sense when the Chorus fills in the blanks.  This moves the play along and helps the audience understand the story better.  The Chorus tells the audience what to feel and when, so it was an invaluable asset to the theatrical experience.