The Giacomini were among the illustrious families in olden days in Florence, and their coat of arms is still to be seen on an angle of this beautiful little palace. Messer Gherardo Tebalducci, a prominent citizen in 1280, had several sons, one of whom, for some unknown reason, dropped the family name and adopted his own Christian name Giacomino as a surname, which often occurs in the lists of the Priors. Antonio Giacomini was a brave soldier who in 1498 saved Poppi from falling into the hands of Alviano, four years later he acted as Commissary-General of the forces in the war with Pisa and the following year he was sent with 500 men into the Romagna against the Venetians. In 1504 he again fought the Pisans, seized Ripafratta and other strong castles, and then marched against his old antagonist Alviano, who was advancing to the help of Pisa, and routed him at Campiglia. Jacopo Nardi tells us that notwithstanding such great services the Republic of Florence let her old servant die in extreme poverty.

The Giacomini were zealous upholders of freedom. Francesco, one of the Dieci di Guerra in 1529, was so violent in his hatred of the Medici, that he denounced Carlo Cocchi for saying that it would be better not to expose the city to the horrors of a siege and to capitulate at once, because after all she belonged to the Medici. This ill-considered speech cost Cocchi his life. Another of the Giacomini, taken prisoner at Montemurlo with Filippo Strozzi, was beheaded in the Bargello.

A branch of the family must however have been fortunate in trade, as Settimanni notes in his Diary, “on the 10th October, 1580, the beautiful house of the Giacomini at S. Michele degl’Antinori was begun.” It is curious that neither he nor any other contemporary writer gives the name of the architect of the “Palagetto degl’ Giacomini,” as the Florentines lovingly called the building they admired so much, but it is most probably the work of Giovanni Battista Dosio of San Gemignano. It remained in the possession of the family until the death of Lorenzo, last of the Giacomini, in 1764, who left it to his widow for life and then to the Michelozzi Boni. After passing through various hands the palace was bought in 1839 by Count F. de Larderel, a Frenchman who made a large fortune in borax at Volterra, and whose daughter Countess Mirafiore now owns it.