Francesco Guicciardini, an Italian historian, born in Florence, March 6, 1482, died near that city in May, 1540. At the age of 23 he held a professorship of law, and was afterward appointed ambassador to Ferdinand the Catholic. He was soon called to the court of Leo X., who made him governor of Modena and Reg-gio, which dignity he retained under Adrian VI. Clement VII. sent him to the Romagna, where he succeeded in quelling the conflicts of the Guelphs and Ghibellines. As lieutenant general of the pope he defended Parma against the enemy, and subdued the revolted city of Bologna, after which he retired (1534) to Florence and commenced his history. On the assassination of Alessandro de' Medici, he exerted himself to defeat the project of the senate for restoring the republic. Cosmo de' Medici was made governor by his influence, but soon exchanged this title for that of duke, and assumed absolute power in the state, when Guic-ciardini, who had been attached to him, resigned his office and retired. Of his "History of Italy," the first complete 16 books appeared in 1561, edited by his nephew. A few years afterward four more were added, but these are not complete.

It has since been often reprinted in 20 vols., but the best edition is that by Rosini (10 vols., Pisa, 1819-20). Among the other remains of Guicciardini are Consigli aurei ed avvertimenti politici (translated into French, Paris, 1577), and parts of his correspondence published by Bernigio under the title Con-siderazioni civili sopra Vistoria di Francesco Guicciardini (Venice, 1582), and under that of Legazionc di Spagna (Pisa, 1825).