These events and demonstrations gave the Florentines an earnest of approaching war; they consequently followed their usual practice on similar occasions, and created the Council of Ten.  They engaged new condottieri, sent ambassadors to Rome, Naples, Venice, Milan, and Sienna, to demand assistance from their friends, gain information about those they suspected, decide such as were wavering, and discover the designs of the foe.  From the pope they obtained only general expressions of an amicable disposition and admonitions to peace; from the king, empty excuses for having expelled the Florentines, and offers of safe conduct for whoever should demand it; and although he endeavored, as much as possible, to conceal every indication of his hostile designs, the ambassadors felt convinced of his unfriendly disposition, and observed many preparations tending to the injury of the republic.  The League with the duke was strengthened by mutual obligations, and through his means they became friends with the Genoese, the old differences with them respecting reprisals, and other small matters of dispute, being composed, although the Venetians used every possible means to prevent it, and entreated the emperor of Constantinople to expel all Florentines from his dominions; so fierce was the animosity with which they entered on this war, and so powerful their lust of dominion, that without the least hesitation they sought the destruction of those who had been the occasion of their own power.  The emperor, however, refused to listen to them.  The Venetian senate forbade the Florentine ambassadors to enter their territories, alleging, that being in league with the king, they could not entertain them without his concurrence.  The Siennese received the ambassadors with fair words, fearing their own ruin before the League could assist them, and therefore endeavored to appease the powers whose attack they were unable to resist.  The Venetians and the king (as was then conjectured) were disposed to send ambassadors to Florence to justify the war.  But the Venetian envoy was not allowed to enter the Florentine dominions, and the king’s ambassador, being unwilling to perform his office alone, the embassy was not completed; and thus the Venetians learned, that however little they might esteem the Florentines, the latter had still less respect for them.

In the midst of these fears, the emperor, Frederick III., came into Italy to be crowned.  On the thirtieth of January, 1451, he entered Florence with fifteen hundred horse, and was most honorably received by the Signory.  He remained in the city till the sixth of February, and then proceeded to Rome for his coronation, where, having been solemnly consecrated, and his marriage celebrated with the empress, who had come to Rome by sea, he returned to Germany, and again passed through Florence in May, with the same honors as upon his arrival.  On his return, having derived some benefits from the marquis of Mantua, he conceded to him Modena and Reggio.  In the meantime, the Florentines did not fail to prepare themselves for immediate war; and to augment their influence, and strike the enemy with terror, they, in conjunction with the duke, entered into alliance with the king of France for the mutual defense of their states.  This treaty was published with great pomp throughout all Italy.