Unlike the Medici, they were of the old Florentine nobility, tracing their line traditionally from the legendary Philippi, said to have been ennobled by Charlemagne himself, in 805; from him the Strozzi and the Gualfreducci also claimed their descent.
Simon de Gondi renounced the Ghibelline party for himself and his house, in 1351; he loaned the Republic 8000 golden florins in a time of extremity.
Giuliano, who built the palazzo, had refused a pension offered him by the King of Naples, because he did not consider that the citizen of a free republic could accept money from a foreign prince with honour.
The founder of the French Gondi was Alberto (Albert), who settled in Lyon about 1505 as a member of an established Florentine community or nation, of merchants and bankers.
Henri III installed himself in this house in order to conduct the siege of Paris during the Wars of Religion, and here he was assassinated by the monk Jacques Clément.
As a consequence of their prominence, the Gondi archives are of outstanding importance to the historian of economics; they were described by Roberto Ridolfi, Gli archivi delle famiglie fiorentine (Florence: Olschki) 1943.