Leo Aiolia was a Gold Saint during the 12th century.
Aiolia was the brother and apprentice of the renowned Aiolos, for whom he had an admiration. However, Saga tried to kill Athena, disguised as pope, and blamed Aiolos (that tried to prevent Saga from committing such barbarity). Oil instead of being praised, was rejected for being the brother of Aiolos, and that made her wonder if turned into shame. Aiolia vowed to be a strong man to redeem himself with Athena and the sanctuary, the sins that his brother did.
Friend of Marin and Seiya
Aiolia never revealed Seiya who was a gold saint, and Seiya always admired him for his strength and nobility. He always followed Seiya and Marin in your workouts, and always hated wickedness made by the pope's servants, but still saw him as a pure being. Aiolia followed blindly the Saga orders, and was sent to kill Seiya, but gave him a chance to survive because he is his friend; but after Seiya wear the cloth of his brother, Aiolia decides up fighting seriously against Seiya.
Aiolia discovers that the pope is malignant (and ask forgiveness for hate Aiolos) and will immediately face it, though, Shaka intervenes and fighting Aiolia, who during the struggle, is reached brainwashed the Pope.
Seiya goes to Leo Temple, hoping Aiolia or let go, but Aiolia says it will kill Seiya, and strangely does not explain why. Cassios arrives on the scene, and commits suicide to Aiolia to take the trance, however, Aiolia only back to normal, when Seiya hit him. Aiolia then discovers that the evil one pope, was Gemini Saga.
Aiolia was always a good man, noble, and strong; this was why he hated the betrayal of his brother Aiolos. But in the course of the series, Aiolia shows that hated his brother, precisely because of hate who is malignant, and being impulsive. In the Soul of Gold series, Aiolia is more serious and more friendly, not as vindictive (despite being vindictive enough to Dohko think he was impulsive); it appears to be a hard man to attract.