She was the natural daughter, later legitimized, and the only child of the Florentine nobleman, politician and banker Jacopo de' Pazzi.

[1][2] Her mother's name is unknown and Caterina was raised by her father's legitimate wife, Maddalena Serristori, who failed to have any own children.

[2][3] In April 1478 her father, her tutor, and two of her cousins, Francesco and Renato, were executed, among others, following the failure of their conspiracy against the Medici brothers, Lorenzo and Giuliano, governors de facto of the city of Florence.

The rest of the men of Pazzi family was exiled, their family name condemned to damnatio memoriae and the women condemned to chose if enter a convent or continue to live in Florence but renounce the right to marry.

[3] Caterina lived a life of repentances and deprivations, dying on 23 August 1490 at age twenty-seven.