- Ezio: "DO YOU LOVE HER? Cristina! The woman you're about to marry!"
- Manfredo: "Yes, I do! I swear, I do. Kill me here and I will die still loving her."
- ―Ezio Auditore and Manfredo Soderini, 1478.[src]
By 1478, Manfredo was engaged to Cristina, whose father kept pestering her to choose someone to marry. While Cristina deeply loved Ezio Auditore, she had not seen him in two years, leading to her choosing Manfredo as her fiancé.
Manfredo, however, was a gambler and fell deeply into debt. One day, he was confronted by a man whom he owed money to, who cornered him at the end of a bridge under construction, and threatened his life.
Ezio, who had come to Florence to visit Cristina, happened upon the scene and rescued Manfredo from his attackers, before he threatened to kill him with his own hands should Manfredo not be a good husband to Cristina. Manfredo professed that he loved her, and swore he would continue to even should he die there. Some time later, he and Cristina were married, and moved into a residence in Florence.
In 1498, Manfredo and Cristina were attacked by the guards of the "Mad Monk" of Florence, Girolamo Savonarola. In light of the Bonfire of the Vanities, the men condemned their riches and finery, and in the struggle, Manfredo was mortally wounded.
After Cristina fled with the guards in pursuit, Ezio Auditore chanced upon the dying Manfredo. With his final breath, he told Ezio what had happened to Cristina, in a last-ditch effort to see her safe.
- In Assassin's Creed: Renaissance, Manfredo's surname was "d'Arzenta".
- Manfredo is an Italian variant of the name Manfred, itself combination of Germanic magan, "strength" and frid, "peace." The surname Soderini is shared with several influential members of Florentine politics and society during the Renaissance.
- Manfredo wore clothes that resembled Ezio's in his younger days, with a similar bracelet on his right arm and a similar vambrace on his left.