What is the Trojan Saga?

The Trojan Saga refers to the events that led to the Trojan War, the events which occurred during the war, and the aftermath of the conflict.
The Trojan War was a conflict between the Achaeans (Greeks) and the inhabitants of Troy, a territory that, according to archaeological research, is located in what is now Turkey.
According to myth, the conflict originated with Zeus, king of the gods. He had decided to start a war to decimate portions of the human population. Zeus himself had contributed to the creation of more people, given his tendency to mate with mortals. In one instance, this led to the birth of the god Dionysus, the god of wine and revelry.
He decided to organize a feast to celebrate Peleus's and Thetis's marriage. Peleus was a great warrior who became the father of Achilles—an even great warrior and a key figure in the Trojan War. Thetis was a nymph loved by both Zeus and Poseidon. She married Peleus and later gave birth to Achilles.
All of the gods and goddesses (except for Eris) were invited to the party. Eris, the goddess of strife, was stopped at the door by Hermes, the god of messengers who often worked for Zeus personally. Eris was furious. Before she left, she insisted on leaving a gift, which she threw at the guests. It was a golden apple, sometimes called The Apple of Discord. She had inscribed the following words into its skin: "to the fairest." Three goddesses—Aphrodite, Athena, and Hera—assumed ownership of the apple and began to argue over who was its rightful possessor. They insisted that Zeus decide, but he refrained to avoid the goddesses' wrath. He decided that Paris—son of the Trojan king, Priam—should decide.
The goddesses first tempted the young prince by revealing their nude bodies. When he still could not decide on the "fairest" goddess, they each offered him a different prize. Hera, queen of the gods and Zeus's companion, offered to make him the ruler of Asia. Athena, Zeus's daughter who sprang from his head, offered Paris great wisdom as well as the skills of a great warrior. Aphrodite, however, offered the most irresistible present of all: the most beautiful woman in the world. Paris selected Aphrodite's offer.
At the time, Helen of Sparta, later known as Helen of Troy, was considered the most beautiful mortal. She was the wife of Menelaus, King of Sparta. Around the time that Cupid shot Helen with an arrow, causing her to fall in love with Paris, Achilles was born. When he was still an infant, Thetis took him to the River Styx, one of the rivers that flowed in the underworld. She dipped him in its waters to make him invulnerable to physical harm. However, she neglected his heel.
After Menelaus returned home, he realized that Helen had left him. He called on other Achaeans, including his brother Agamemmnon, Achilles, and Odysseus, to go to Troy to retrieve her.
They arrived in a fleet. The war that ensued lasted for nine years. The gods took sides and aided in the conflict. The Trojan War is chronicled in Homer's Iliad, an epic which covers the beginning and end of the war. Much of the text reads like an inventory of loss. Homer tells us which Greek and Trojan soldiers died and how. However, in some books of the epic, he tells us about the relationships the soldiers had with one another and with their families. Patroclus, for example, was the dearest friend of Achilles. Patroclus was killed in battle by Hector. Out of a desire for revenge, Achilles killed Hector. He then dragged his body in front of the city walls with his chariot. King Priam of Troy, who was also Hector's father, pleaded with Achilles for the return of his son's body so that Hector could receive proper burial. Shortly thereafter, Paris killed Achilles with a poisoned arrow directed at Achilles's vulnerable heel. Apollo, who had taken the Trojan side, guided the arrow.
Despite the deaths of its most prominent warriors, the conflict continued to rage. Odysseus ultimately came up with the idea to end it for good: the Greek soldiers would hide inside of a hollow wooden horse, which they would present as a gift to the Trojans. Once the Trojans accepted the gift, they would cast off the horse and murderously attack as many Trojans as possible. The plan worked. The Trojans accepted the "gift" from the Greeks. Later, at night, the Trojans feasted and drank. The Greeks emerged from the horse at this carefree moment and started killing the inebriated Trojans. There was one final battle that succeeded this sudden attack, in which many soldiers died, but the effort was not enough to save Troy, which soon fell. The Greeks destroyed Troy and even burned its temples—an act which offended the gods. As a result, the Greeks could not return home, at least not easily. This obstacle is presented in Homer's Odyssey, which chronicles all of the troubles that Odysseus and his fellow Greek soldiers experienced as they attempted to sail home—a voyage which took years.
Meanwhile, Aeneas, a former Trojan soldier, fled his broken city along with other Trojan refugees. He carried his father, Achises, on his back. Aeneas's departure led to the founding of Rome, a tale later told by Virgil in his Aeneid.
https://www.greekmythology.com/Myths/The_Myths/Trojan_War/trojan_war.html

https://www.theoi.com/