This act spread terror among the Florentines, who could no longer distinguish friends from foes; the only opposition was made around the triumphant chariot which contained the flags, and around the better part of the defenders, who were disposed rather to purchase for themselves an illustrious death by valour, than their safety by flight. A part of the broken army had taken refuge in the castle of Montaperti. The castle being taken by force, the refugees were cut to pieces. It is not easy to ascertain the number of killed in a battle, since the conquerors always exaggerate it, and the conquered conceal it; the latter, or the Florentine writers, acknowledge only twenty-five hundred killed, and fifteen hundred prisoners--but the number must have been far greater. This battle is reckoned among the most bloody of those times, and was fought on the 4th of September, 1260. The Sienese celebrated the victory with solemn pomp, in which the triumphant chariot (_carroccio_) of the Florentines was seen dragged upon the ground, and the name of City of the Virgin was taken by Siena on this occasion, as a devout attestation of gratitude to heaven for the happy issue.[d] The Florentine Guelfs found themselves too much weakened by the defeat of Montaperti to maintain themselves in Florence. The circumference of the walls was too vast, and the population too much discouraged by the enormous loss which they had experienced to admit of defending the city. All those accordingly who had exercised any authority in the republic--all those whose names were sufficiently known to discover their party--left Florence for Lucca together, on horseback. The Guelfs of Prato, Pistoia, Volterra, and San Gemignano could not hope to maintain their ground when those of Florence failed. All abandoned their dwellings and joined the Florentines at Lucca. That city granted to the illustrious fugitives the church and portico of San Friano and the surrounding quarter, where they pitched their tents. The Ghibellines entered Florence on the 27th of September, immediately abolished the popular government, and formed a new magistracy, composed entirely of nobles, who took the oath of fidelity to Manfred, king of the Two Sicilies.