This noble palace, with its arched windows and its beautiful loggia supported by fine columns, was built for Rinieri Dei towards the end of the XVth century by Cronaca, on the site of houses belonging to the ancient family of Bischieri. The lantern at the corner resembles those of the Strozzi palace, and is probably by the famous Niccolò Grosso, surnamed il Caparra.

The first of the Dei family to attain eminence in Florence were Giovanni di Deo, one of the twelve Buonomini in 1445, and his brother Domenico, ambassador to the Court of Naples. Miliano was a Prior in 1743, and his brother Benedetto went, amongst other places, as ambassador to Constantinople, where he stayed seven years and was so trusted by the Sultan that he despatched him on a mission to Damascus. He has left an interesting chronicle of contemporary events in Florence. The magnificent palace at the corner of the Piazza S. Spirito was let in 1568 by Rinieri’s son for two years to Don Garcia di Toledo, brother of Eleonora, wife of Cosimo I. Giovanni, last of the Dei family, died in 1683, and left his patrimony to the Buonomini di S. Martino, a confraternity which still exists and does much good among the poor who are ashamed to beg. They sold the palace the following year to Donato Guadagni.

Progenitor of the Guadagni, according to Passerini,41 was Guittone, son of Migliore of S. Martino di Lubaco, a village on the slopes of Monte Croce in the diocese of Fiesole. The Guadagni arms, a cross edged with thorns, confirms this, that particular spot being called Croce alla Spina. Ser Guadagno di Guitto, his descendant, must have attained a foremost position in Florence, as he was one of the three Priors of Guilds who, together with the Consuls, ruled the city in 1204, and his son Gianni was an Elder fifty years later. The Guadagni were Guelphs; and Gianni and his young son Pierotto fought at Montaperti in 1260, and were exiled with so many of the other great Florentine families. On the return of his party to power, Pierotto, who was one of the richest bankers in Florence, was twice elected Gonfalonier of Justice; but before his death in 1298 the bank failed, and his palace close to the Duomo, near the old Porta a Balla, was let to Antonio Orsi, the warlike Bishop of Florence.

The Guadagni seem to have been a hot-headed, quarrelsome race. Migliorozzo fought with distinction against Henry VII, and again at Montecatini and at Altopascio. In 1327 he attacked and wounded his cousin Gherardo, and then attempted to poison him and his wife. The latter died from the effects of the poisoned cakes, and Migliorozzo was fined and condemned to lose his right hand and his left foot, but was pardoned at the intercession of Gherardo. Lapo Guadagni was beheaded in 1344 for attempting to assassinate his cousin Filippo and killing a priest who defended him. In 1410 Antonio Guadagni also lost his head for trying to defraud the Commune of Florence by swearing that a certain Gaspero was the son of Francesco da Carrara, Lord of Padua, who had been strangled by the Venetians, to enable him to draw out money deposited by his supposed father in the Monte.

Bernardo Guadagni is well known as the man whose debts were paid by Rinaldo degl’Albizzi, in order that he might be elected Gonfalonier of Justice and sentence Cosimo de’ Medici to exile, who only escaped a worse fate by bribing the Gonfalonier. Antonio, his son, fought with distinction against both Visconti and Paolo Guinigi, Lord of Lucca, but the return of Cosimo in 1434 was fatal to all the adherents of the Albizzi. Declared a rebel for not taking up his residence in Barcelona, to which place he was exiled for ten years, Antonio was taken prisoner at Fermo in 1436 and beheaded. The curious thing is that twenty-two years later he was again condemned to death as a rebel, and the sentence had to be revoked as impossible of execution against a dead man. A cousin of his, Tommaso, born in Savoy and married to a Frenchwoman, made so large a fortune by trade that “riche comme Gadagne” became a proverbial saying in Lyons, where he built a magnificent hospital and a fine house in the street named after him. He left his money and many domains to his nephew and namesake, whose descendants became French citizens with French titles, Conte de Verdun, Baron de Beauregard, de Champeroux, etc.

Jacopo, a nephew of Tommaso, remained in Italy, and bowed his neck to the yoke of the Medici. He was made a Senator in 1561 by Cosimo I. and occupied himself, as did also his two sons, in adorning the Guadagni palace near the Duomo. His grandson, Pierantonio, began the splendid gallery, the library and the museum of antiquities, which became famous in the XVIIIth century and in the beginning of the XIXth, after his father had bought the splendid old palace of the Dei. Ortensia Guadagni married a nephew of Pope Leo XI. and after his death became lady-in-waiting to Vittoria della Rovere, Grand Duchess of Tuscany, whose education she had superintended. Created a Marchioness in her own right, an unheard-of thing in the Grand Duchy, she was invested with the feudal estate and castle of S. Leolino del Conte, with the obligation of furnishing sixty-nine soldiers to the State, and was allowed to leave her title to her brother Tommaso’s eldest heirs male. He it was who employed Gherardo Silvani to build the palace which afterwards passed into the possession of the Dukes of San Clemente (see p. 303), and his son Francesco was a patron of the arts and an intimate friend of Salvator Rosa. Alessandro, great-nephew of the Tommaso Guadagno who settled in France, assassinated Andrea Davanzati in 1566, and was condemned to death in contumaciam. After some years Catherine de’ Medici obtained his pardon from her uncle the Grand Duke Francesco I., and he returned to Florence, where he built, after the design of Gherardo Silvani, says Passerini, a fine palace on the site of the old houses of his family on the Piazza del Duomo, which now belongs to the Marchese Strozzi of Mantua. Baldinucci, however, only mentions the coat-of-arms on the palace as being the handiwork of Silvani. Marquess Neri Guadagni, who died in 1862, left an only daughter, married to Marchese Dufour Berte, whose son now owns the great palace in Piazza S. Spirito.