Agamemnon was one of the combatants of the Trojan War. He was a son of Atreus, King of Mycenae and Aerope, Princess of Crete. His paternal grandparents were Pelops, King of Pisa and his wife Hippodamia. His maternal grandparents was Catreus, King of Crete. Pelops was a son of Tantalus and Catreus a son of Minos. Both Tantalus and Minos were sons of Zeus and paternal half-brothers to each other. Hippodamia was a daughter of Oenomaus, King of Pisa. Her paternal grandfather was Ares, another son of Zeus.
King Atreus of Mycenae, having a serious feud with his brother Thyestesdecided to arrest him. For this purpose he sent his sons, Agamemnon and Menelaus to seize Thyestesin Delphi and bring him to Mycenae. While Thyesteswas in prison, Atreus conspired to murder him but, having made false judgements, he was himself killed, and Thyestessucceeded him on the throne.As a result, the Atrides (sons of Atreus) Agamemnon and Menelaus went into exile. At first they stayed with Polyphides, King of Sicyon but later they were received in Aetolia by Oeneus, King of Calydon. Not long afterwards, when they thought the time was ripe to dethrone Mycenae's hostile ruler , they returned and with the help of Tyndareus, King of Sparta they succeeded in deposing Thyestes. They drove their uncle to seek refuge at Cythera, an island off the southern coast of the Peloponnesus.
When they had thus seized power, the Atrides married the daughters of Tyndareus. Agamemnon rose to the throne of Mycenae and married Clytaemnestra, eldest of the sisters. Menelaus married Helen and became heir to the throne of the Sparta. He succeeded his father-in-law as planned, However according to some accounts Clytaemnestra was already a widow. She had previously married a younger Tantalus, son of Thyestes. They had a child together. Agamemnon only married her after killing Tantalus and their child. Clytaemnestra would never forget or forgive the death of her first child.
A few years later, Menelaus visited Crete to attend the funeral of Catreus. In his absence, Paris, prince of Troy visited Sparta and left with Helen and much of Menelaus' property. Agamemnon and Menelaus met at Mycenae, deciding to raise an army against Troy. So heralds were sent to all kings of Hellas reminding them of "The Oath of Tyndareus " they had sworn, which bound them to support Menelaus if ever his marriage with Helen was threatened. This is how Agamemnon, who at the time was the most powerful ruler in Hellas, became the commander in chief of a large coalition, whose war-ships gathered in Aulis—a Boeotian harbour opposite the island of Euboea—in order to sail to Troy and have Helen and the property restored, either through negotiation or by force.
However, the mighty fleet could not sail because of the winds, and as impatience grew in the army, the seer Calchas found the remedy to this inconvenience. He declared that they would be able to sail only if Agamemnon sacrificed his daughter Iphigenia to Artemis, and if he did, they would also take the city of Troy, but if he did not, they would neither sail nor sack the city. Artemis was assumed to be angry at Agamemnon because he had said, on shooting a deer, that the goddess herself could not have done it better, and also because Agamemnon's father Atreus Ahad not sacrificed to her a certain golden lamb.
Agamemnon is said to have thought of disbanding the army, for even if the ruler could accept the price, the father could not. But Menelaus, eager to be avenged and to have his own wife and property restored, persuaded his brother to become the murderer of his own daughter. So Agamemnon sent a deceitful letter to Clytaemnestra and their own child, asking them to come and join him in Aulis, where Iphigenia, he said, was going to be given in marriage to Achilles. Achilles himself was not aware of the way the king was using his name, for the lie was only known by Agamemnon, Menelaus, Calchas and Odysseus. Lured by the master of their own house,Clytaemnestra and Iphigenia came to Aulis, where murder, disguised as wedding, awaited the young girl. Some have said that this was a very serious dilemma that Agamemnon had to solve, for it is never easy to commit great crimes. Nevertheless the king prevailed over the father. Iphigenia was sacrificed and, if Calchas the seer is to be believed, the fleet could sail from Aulis to Troy thanks to that deed. But Clytaemnestra never forgave the loss of her daughter.
Yet it is also told that when Iphigenia was about to be sacrificed in Aulis, she vanished, being saved by Artemis, who substituted for her a deer at the altar and transported her to Tauris. Later, while being a priestess of Artemis in Tauris, Iphigenia saved her brother Orestes' life. Iphigenia who has also been said to have been made immortal by the goddess, was not, according to some, the daughter of Agamemnon and Clytaemnestra but of Theseus and Helen. They assert that, when Helen was restored to Sparta by the Dioscuri ,her brothers, following her brief marriage to Theseus the young woman was pregnant. She gave birth to Iphigenia and gave her to Clytaemnestra to be brought up as the latter's daughter.
In the tenth year of the Trojan War, Agamemnon captured Chryseis, daughter of Chryses. Her father was a priest of Apollo. Agamemnon intended to keep the girl as a prize, take her home, and turn her into both a slave and a concubine. Chryses, a loving father if compared to the king, came then to see Agamemnon and, having blessed the whole army, offered a generous ransom for his daughter's freedom. The troops applauded the priest, but Agamemnon was not a man inclined to let his will be curbed. So he denied Chrysesrequest and, in an arrogant display of authority, threatened the old man, who left the Achaean camp humiliated. The best time to address the gods is when humans refuse to listen, so Chrysesprayed to Apollo as soon as he found himself alone. He asked the god to let the Achaeans pay through his golden arrows the tears he was shedding. That is why Apollo, who otherwise is known as the bright one, on hearing the prayer and learning the outrage his priest had suffered, came down from Olympus, as they say, darker than night, letting his arrows rain on the Achaean camp, which means that an epidemic spread in the army, taking many lives.
As the plague was out of control, an assembly was called, in the course of which the seer Calchas declared that the reason for the pestilence was to be found in Apollo's anger, in turn caused by Agamemnon's insults. These were bad news for the king, who first called Calchas "prophet of evil". Nevertheless he accepted to give up his beautiful prize, provided another fresh one was found to replace Chryseis. And if it couldn't be found, he said, he would help himself to someone else's prize. Because of this threat, Achilles called the king shameless schemer, and accused him of always taking the lion's share and using others to pile wealth and luxuries for himself. Then the king answered by letting Achilles know that, in the same way that Apollo was robbing him of the beautiful Chryseis he was now going to pay a visit to Achilles tent and, by taking away his sweetheart Briseis, teach him a lesson in power and kingship.
Agamemnon kept his word: he gave up Chryseisand took instead Achilles ' sweetheart Briseis. Thereby he caused the best of his warriors to nurse a wrath which, keeping him away from the battlefield, caused the Achaean army as many losses as those caused by Apollo's plague. That's what Agamemnon's art of ruling achieved. When Chryseiswas set free, she gave birth to a son named Chryses after her father. Some say the boy was a son of Apollo but others call him a son of Agamemnon. On a later occasion, Chrysesas son of Agamemnon, saved the lives of Orestes and Iphigenia in Tauris on account of their family ties.
The conflict with Achilles put Agamemnon at odds with heaven, for the former was the son of a goddess, who obtained of Zeus the promise to teach Agamemnon and the Achaeans a lesson for the outrage her sweet son had suffered, by letting them, if only for a while, be routed by the Trojans. Agamemnon was also deceived by Zeus, who sent him false dreams carrying the message that victory was at hand and he should prepare to attack. It was not before the military situation had considerably deteriorated, that Agamemnon tried to appease Achille's wrath so that he would fight again, by offering him the seven tripods, the seven women, the seven cities, and many other gifts which included Achilles' sweetheart Briseis, whom Agamemnon swore he had not touched—an oath that has never been openly questioned. But Achilles' considered these gifts hateful, for Menelaus' brother had done to him what Paris had done to Menelus, and it was precisely this kind of outrage the Achaeans had come to avenge.
The fight then had to be done without Achilles. Agamemnon, himself a brave man, killed many Trojans. However, in spite of all efforts, the Achaeans got the worst part, and the king himself was wounded in battle by Coon, the eldest son of Antenor. But when the fire reached the ships, Achilles, fearing complete defeat, sent Patroclus with a force of Myrmidons to fight. And when Hectorkilled Patroclus in battle, then Achilles came to life again. Achilles called an assembly of all Achaeans, and in it declared that his wrath was over. As a way of expressing how much he regretted his feud with Agamemnon, he even said that he wished Briseis to have been shot down by Artemis the day he chose her when he sacked Lyrnessus, the city east of Mount Ida. For he felt that because of his refusal to fight, Patroclus, whom he loved far more than Briseis, had been killed by Hector. On hearing this, Agamemnon declared that it had been wrong to confiscate Achilles sweetheart, but he was not to blame, for surely it was Ate who had blinded his judgement, and every man knows that she is capable of deluding Zeus himself. In any case, he acknowledged that since it was him who had been blinded, he was willing to make amends and pay compensation, referring again to the seven tripods, the seven women, the seven cities, and all other gifts that he formerly had offered Achilles. Achilles declined the offers.
So ended the feud between Agamemnon and Achilles. Some have argued that Achilles is to blame, because his duty was to fight against the Trojans, not to spend a nice time in the company of sweet girls. Achilles never received Agamemnon's gifts, which meant nothing to him, for soon after he killed Hector, he was himself mortally wounded by Paris, who in turn was killed by the poisoned arrow which Philoctetes discharged against him. It was the tenth year of the war, the bow and arrows of Heracles were fighting on the Achaean side, Neoptolemus had arrived, and all other conditions to take the city had been fulfilled- So the Wooden Horse was conceived, and Troy was sacked.
When Troy was taken, many Trojan women were made captives, and Cassandra was awarded to Agamemnon, who brought her as a concubine to Mycenae. But on his return, he and his new concubine were murdered by Aegisthus and Clytaemnestra. Aegisthus was a son of Thyestes and first cousin to Agamemnon. He had become the lover of Clytaemnestra who thus placed him on the throne of Mycenae. The murder is usually attributed to Clytaemnestra alon. She ambushed her husband in the bathroom and cut him down with a blade. However other versions name Aegisthus as an accomplice to the murder, not only a beneficiary. Aegisthus and Clytaemnestra would rule side-by-side for the following seven years.