The Oresteia is a trilogy of Greek tragedies written in 458 B.C. for the Dionysia festival. They were written by the Greek playwright Aeschylus, who is often referred to as the Father of Tragedy. The three plays in the Oresteia are Agamemnon, Libation Bearers and The Eumenides.
The play Agamemnon begins with the sacrifice by Agamemnon, who is of the House of Atreus, of his daughter in order to make the winds blow favorably so he can sail to Troy. Upon his return from battle, Agamemnon brings home a hostage, Cassandra. Cassandra is the daughter of the defeated King of Troy and a seer of Apollo. Agamemnon’s wife, Clytemnestra, plays the part of a loving, kind and lonesome wife. However, in reality she is cruel and she is planning her husband’s death.
Soon, both Agamemnon and Cassandra are killed by Clytemnestra. She has two reasons for killing her husband: to avenge her daughter’s death and to marry Aegisthus, Agamemnon’s cousin. She kills Cassandra out of jealousy. Cassandra has foreseen her own death and the fall of the House of Atreus, but because of a curse from Apollo, no one believes her.
Aegisthus then comes to rule with Clytemnestra.
There is a warning by the Chorus (narrators) that Agamemnon’s banished son, Orestes, will come to avenge his father.