Early life

 

Ezio was born in Florence on 24 June 1459, as the second son of Giovanni and Maria Auditore. He appeared to be stillborn, but, after some words of encouragement from his father, he began to cry, leading his father to call him a "fighter".
Up until the age of 17, Ezio lived a life of luxury amidst the members of the Florentine noble class; he was apprenticed to the renowned banker Giovanni Tornabuoni, who worked alongside Giovanni Auditore's banking business, but was all the while unaware of his father's allegiance to the Assassin Order.
In the year 1476, Ezio, his older brother Federico, and friends of the family fought with Vieri de' Pazzi and his gang. Just before the fight, Ezio received a gash down across his lip – caused by Vieri throwing a stone – which would scar, and remain for the rest of his life.

Ezio obtaining the scar on his lip

During the brawl, Ezio pummeled several members of the opposing gang, but Vieri managed to flee the scene before Ezio could do anything to him. After looting several people left unconscious by the fight, the two brothers ran across the rooftops to find Ezio some medical help for his injuries.
After the doctor tended to his wound, a church nearby caught the eye of the brothers, and Federico suggested a race. Ezio won, as he managed to reach the top quickest, and together the two looked out over the city. Despite Federico's disapproval, Ezio made his way to the home of Cristina Vespucci and spent the night with her.
Though caught by Cristina's father the morning after, Ezio fled from a group of pursuing guards before meeting with his father at the Palazzo Auditore. Giovanni scolded him, but later softened, admitting that his son's actions reminded him of his own youth. He then asked Ezio for his assistance in an errand later in the day.

Ezio's initial meeting with Leonardo da Vinci

Once Ezio had returned home, Ezio's little brother Petruccio asked him if he could collect eagle feathers from the rooftops, with the promise to return to bed afterwards, as he was ill. After a tiring search for feathers, Ezio returned them to his younger brother, though Petruccio was secretive about their purpose.
Later, Ezio found his sister Claudia in a distraught state, crying on a bench in their home after discovering her boyfriend, Duccio de Luca, had been unfaithful. After obtaining his whereabouts, Ezio tracked down and beat Duccio, before warning him to stay away from his sister.
Upon returning to the palazzo once more, Ezio's mother secured his services in picking up some paintings from a young artist that she patronized, Leonardo da Vinci. On the walk home, Leonardo struck up a conversation, beginning a friendship between the two young men that would last throughout their later lives.