In Greek mythology, Agamemnon (Ancient Greek: Ἀγαμέμνων; modern Greek: Αγαμέμνονας, "very steadfast") was the son of King Atreus and Queen Aerope of Mycenae, the brother of Menelaus, the husband of Clytemnestra, and the father of Electra and Orestes. Mythical legends make him the king of Mycenae or Argos, thought to be different names for the same area. When Helen, the wife of Menelaus, was abducted by Paris of Troy, Agamemnon commanded the united Greek armed forces in the ensuing Trojan War.

On Agamemnon's return from Troy he was murdered (according to the fullest version of the oldest surviving account, Odyssey Book 11, l.409f.) by Aegisthus, the lover of his wife Clytemnestra. In old versions of the story: "The scene of the murder, when it is specified, is usually the house of Aegisthus, who has not taken up residence in Agamemnon's palace, and it involves an ambush and the deaths of Agamemnon's followers too". In some later versions Clytemnestra herself does the killing, or they do it together, in his own home.

In Greek mythology, Helen of Troy (in Greek, Ἑλένη, Helénē), also known as Helen of Sparta, was the daughter of Zeus and Leda (or Nemesis), step-daughter of King Tyndareus, wife of Menelaus and sister of Castor, Polydeuces and Clytemnestra. Her abduction by Paris brought about the Trojan War.

The etymology of Helen's name has been a problem to scholars until the present. Georg Curtius related Helen (Ἑλένη) to the moon (Selene Σελήνη). Émile Boisacq considered Ἑλένη from the noun ἑλένη meaning "torch". It has also been suggested that the λ of Ἑλένη arose from an original ν, and thus the etymology of the name is connected with the root of Venus. Linda Lee Clader, however, says that none of the above suggestions offers much satisfaction.

If the name has an Indo-European etymology, it is possibly a suffixed form of a root *wel- "to turn, roll", or of *sel- "to flow, run". The latter possibility would allow comparison to the Vedic Sanskrit Saraṇyū, a character who is abducted in Rigveda 10.17.2. This parallel is suggestive of a Proto-Indo-European abduction myth. Saraṇyū means "swift" and is derived from the adjective saraṇa ("running", "swift"), the feminine of which is saraṇā; this is in every sound cognate with Ἑλένα, the form of her name that has no initial digamma. The possible connection of Helen's name to ἑλένη ("torch"), as noted above, may also support the relationship of her name to Vedic svaranā ("the shining one").