The two centuries which are treated in this volume constitute [Sidenote: Italy in the fourteenth and fifteenth centuries.] the most brilliant period in Italian history since the age of Augustus. The absence of any central authority, which disappeared even more completely in Italy than in Germany, opened the way for the growth of a number of political organisations, whose history is as fascinating as their variety is bewildering. In addition to the great dynasties of Anjou, Visconti, and Medici, we have to watch the fortunes of the great republics of Venice, Florence, and Genoa, of the temporal states of the Church, and of a number of lesser families, such as the House of Este in Ferrara, the della Scalas in Verona, the Gonzagas in Mantua, the Montefeltri in Urbino, whose kaleidoscopic changes are narrated with such wealth of detail in the volumes of Sismondi. But what gives its special importance to the history of this period is that in it Italy becomes the teacher of Europe. It is to Italy that we trace that great movement, known as the Renaissance, which began with the revival of classical learning, but led on to the growth of national literatures, to the rise of a new spirit in the arts of painting and sculpture, and to the enfranchisement of human thought from the fetters of superstition, routine, and the formulas of scholasticism. In the fifteenth century, Italy originated the art of writing history as distinguished from the compilation of mediæval chronicles. And finally, Italy instructed Europe in politics as well as in letters and art. The foremost European rulers of the sixteenth century learnt the maxims of government from Italian princes and Italian writers: the great states of modern times learnt from Italy the practices of diplomacy and the theory of the balance of power. Political science, which had made no progress since the days of Aristotle, was revived by the writings of Machiavelli and Guicciardini.