➡️ https://en.wikipedia.org/wiki/Discordia

"In Roman mythology, Discordia is the Roman equivalent of the Greek Eris, goddess of strife and discord. [...] Like Eris, Discordia has no mythology other than her involvement in the Judgement of Paris."

➡️ https://en.wikipedia.org/wiki/Paris_(mythology)#Judgement_of_Paris

"In celebration of the marriage of Peleus and Thetis, Lord Zeus, ruler and a chief deity of the Greek pantheon, hosted a banquet on Mount Olympus. Every deity and demi-god had been invited, except Eris, the goddess of strife (no one wanted a troublemaker at a wedding). For revenge, Eris threw the golden Apple of Discord inscribed with 'For the most beautiful' into the party, provoking a squabble among the attendant goddesses over for whom it had been meant.

The goddesses thought to be the most beautiful were Hera, Athena, and Aphrodite, and each one claimed the apple. They started a quarrel so they asked Zeus to choose one of them. Knowing that choosing any of them would bring him the hatred of the other two, Zeus did not want to take part in the decision. He thus appointed Paris to select the most beautiful.

Escorted by Hermes, the three goddesses bathed in the spring of Mount Ida and approached Paris as he herded his cattle. Paris was frightened at the appearance of the deities, but Hermes assured him it was the will of Zeus. Some artistic depictions have the goddesses appear unclad before the mortal. Still, Paris could not decide, as all three were ideally beautiful, so the goddesses attempted to bribe him to choose among them. Hera offered ownership of all of Europe and Asia. Athena offered skill in battle, wisdom and the abilities of the greatest warriors. Aphrodite offered the love of the most beautiful woman on Earth: Helen of Sparta. Paris chose Helen and thereby Aphrodite.

However, Helen was already married to King Menelaus of Sparta. When Menelaus was away from home, Paris seduced Helen into running away with him. In the Iliad, Helen notes how she had followed Paris to Troy, and Apollodorus describes the pair taking valuables together. Some sources claim Paris had to raid Menelaus's house to steal Helen from him, but others say he was first welcomed in.

The Spartans' expedition to retrieve Helen from Paris in Troy is the mythological basis of the Trojan War. This triggered the war because Helen was famous for her beauty throughout Achaea (ancient Greece), and had many suitors of extraordinary ability. Therefore, following Odysseus's advice, her father Tyndareus made all suitors promise to defend Helen's marriage to the man he chose for her. When Paris took her to Troy, Menelaus invoked this oath. Helen's other suitors, who between them represented most of Achaea's strength, wealth, and military prowess, were obliged to help bring her back. Thus, the whole of Greece moved against Troy in force and the Trojan War began."

Why did I quote this?

Whoever Discordia/Eris is, she was able to manipulate the "gods" into starting a war... with an apple.

Let that sink in.