According to mythology, Nafplio was named after Nauplius, the founder of the city, who was son of Poseidon and Amymone. Nafplio was also the birthplace of Palamedes, the local mythical hero of the Trojan War, who supposedly invented weights and measures and invented the Greek alphabet.
Palamedes was killed in the Trojan War by his fellow Greeks, as a result of Odysseus' treachery. Nauplius went to Troy to demand justice for the death of his son, but met with no success. Consequently, Nauplius sought revenge against King Agamemnon and the other Greek leaders. He caused many shipwrecks of heroes returning from War. Nauplius also somehow induced the wives of three of the Greek commanders to be unfaithful to their husbands, including Agamemnon's wife Clytemnestra
The mythical founder of Mycenae is Perseus, son of Zeus and Dana, daughter of Akrisios, king of Argos. Perseus named the new city Mycenae after the pommel (mykes) of his sword, which fell there, or after the Persia spring, discovered there under the root of a mushroom (mykes). According to the myth, Perseus’s descendants reigned at Mycenae for three generations. After the last of them, Eurystheas, died childless, the Mycenaean chose Atreus, son of Pelops, father of Agamemnon and Menelaus, as their king.
Mycenae became the kingdom of the legendary Agamemnon, ruler of the Greeks in the Trojan War. After Helen was taken from Sparta to Troy, her husband, Menelaus, asked his brother Agamemnon for help. Greek forces gathered at Aulis. However, consistently weak winds prevented the fleet from sailing on the ocean. Through a subplot involving the gods and omens, the priest Calchas said the winds would be favorable if Agamemnon sacrificed his daughter Iphigenia to the goddess Artemis. Agamemnon persuaded his wife Clytemnestra to send Iphigenia to him, telling her he was going to marry her to Achilles. When Iphigenia arrived at Aulis, she was sacrificed, the winds turned, and the troops set sail for Troy. The Trojan War lasted ten years. Clytemnestra and her lover Aegisthus killed Agamemnon upon returning and his concubine, the Trojan princess Cassandra.
Then Aegisthus replaced Agamemnon as king and ruled for seven years with Clytemnestra as his queen. They had three children: a son Aletes, and daughters Erigone and Helen. Clytemnestra was eventually killed by Orestes, her son by Agamemnon.