|Paternal Grandfather:||Cosimo Medici|
|Portrayed by:||Tom Bateman|
|First Appearance:||The Hanged Man|
|Latest Appearance:||The Blood of Brothers|
Giuliano is a dashing bon vivant who enjoys the spoils of his position while letting his older brother shoulder the burdens of leadership. Initially, Giuliano expresses a dislike for da Vinci that stems from envy and because da Vinci exposes Giuliano’s insecurity from not being taken seriously.
Da Vinci is everything Giuliano is not – brilliant and unbound by social convention. Plus, he has Lorenzo’s favor, which is something Giuliano has always craved. But his crude jealousy also gives him one advantage over da Vinci. He’s not blinded by da Vinci’s dazzling genius, as most people are. In his own, simplistic way, Giuliano senses something that Lorenzo, Lucrezia and others do not - that da Vinci’s real allegiance is to his quest for knowledge and his mother. What Giuliano rightly intuits is that when those things come into conflict, Florence will always lose out.
While Lorenzo arranges a match for his brother, Guiliano engages in an affair with Vanessa Moschella. After his uncle is executed as a traitor and Vatican spy, Guiliano is determined to find out who the real spy was. He realizes it is his brother's mistress and goes after her, only to find her being attacked by Vatican assassins. Lucrezia then stabs Guiliano and leaves him for dead when he berates her for what she has done. Guiliano survives, and manages to return to Florence to expose a conspiracy against his family. He fights his enemies, but his mortally stabbed. Before he dies in Vanessa's arms, she tells him she is carrying his child.
He reappears as a shadow to both Da Vinci and his brother, respectively to remind Da Vinci to watch over Vanessa and his child, and to urge Lorenzo to fight on.
- Brother of: Lorenzo Medici
- Brother-in-law of: Clarice Orsini
- Lover of: Vanessa Moschella
- Protégé of: Gentile Becchi
- In real life, Guiliano had a son by his mistress who was born after his father's death as a result of the Pazzi conspiracy. That son would go on to become Pope Clement VII.