II.
Towards the end of the thirteenth century the Republic had acquired very high importance throughout Italy as well as Tuscany. The fall of the Hohenstauffens, the coming of the Angevins, the vacancy of the Imperial throne had given an enormous ascendancy to the Guelph party which in Florence was that of the democracy. Its three great Ghibelline rivals, Pisa, Sienna, and Arezzo, had been humiliated and conquered by the subtle diplomacy of Florence and Florentine arms; and these victories had not only re-established the Republic's political authority in Tuscany, but opened and secured to it all the chief highways of commerce. Through Pisa it had access to the sea; through Sienna and Arezzo, to Rome, Umbria, and Southern Italy; it could pass to the north through distant Bologna, peopled with friendly Guelphs. Accordingly the commerce of Florence was then rapidly increased, and this republic of merchants, surrounded by other republics equally devoted to trade and industry, stood at the head of all Tuscany. On the other hand, however, the augmented power of the Angevins was beginning to excite the jealousy of the Popes who had first called them to Italy, and who now turned their eyes towards Germany in order to revive the Imperial pretensions, and thus check the growing ambition of the French king. For Charles of Anjou, whom they had named Senator of Rome and Vicar-Imperial of Tuscany, now seemed determined to follow the daring policy of the Swabian line by aspiring to supremacy over Italy.
During this state of things, the Florentines managed to keep their balance with marvellous finesse, and by leaning this way, or that, frequently turned the scales on the side they preferred. They utilised the king's soldiery to crush Ghibelline cities and Ghibelline nobles; they leaned on the Pope, to check Charles's arrogance; and they showed readiness to favour the Empire, when the Pope tried to assert temporal supremacy, as though, in the present interregnum, he were the natural inheritor of the imperial rights. By this means, the Republic not only preserved its independence, but became a State commanding the fear and respect of all Italy.[421] This was all the result of the shrewdness, energy, and intelligence of its burghers, who governed with so much thriftiness and wisdom as to achieve an unparalleled prosperity. "It is a known thing," says Villani, "that down to this time and for long past, such was the tranquillity of Florence, that the City gates stood unlocked by night,[422] no duties were exacted in Florence;[423] and rather than impose burdens, when money was needed, old walls and bits of land within and without the City were sold to the owners of conterminous portions of the soil."[424] With few taxes and no debts, the administration was excellently conducted; it left the citizens unhampered, and increased the general well-being.