The House of Strozzi is the name of an ancient Florentine family, who like their great rivals the Medici family, began in banking before moving into politics. Until its exile from Florence in 1434, the Strozzi family was by far the richest in the city, and was rivaled only by the Medici family, who ultimately took control of the government and ruined the Strozzi both financially and politically. This political and financial competition was the origin of the Strozzi-Medici rivalry. Later, while the Medici ruled Florence, the Strozzi family ruled Siena, which Florence attacked, causing great animosity between the two families. Soon afterward, the Strozzi married into the Medici family, essentially giving the Medici superiority.

The House of Medici was an Italian banking family and political dynasty that first consolidated power in the Republic of Florence under Cosimo de' Medici, during the first half of the 15th century. The family originated in the Mugello region of Tuscany, and prospered gradually until it was able to fund the Medici Bank. This bank was the largest in Europe during the 15th century and facilitated the Medicis' rise to political power in Florence, although they officially remained citizens rather than monarchs until the 16th century.