The feud between Guelph Florence and Ghibelline…
1260 CE
The feud between Guelph Florence and Ghibelline Siena comes to a head in September, 1260, when the Florentines, supported by their allies from around Tuscany (Bologna, Prato, Lucca, Orvieto, San Gimignano, San Miniato, Volterra and Colle Val d'Elsa), move an army of some thirty-five thousand men towards Siena.
The Sienese call for help from King Manfred of Sicily, who provides a contingent of German mercenary heavy cavalry.
The Sienese forces are led by Farinata degli Uberti, an exiled Florentine Ghibelline.
Even with these reinforcements, though, they can only raise an army of twenty thousand.
The ensuing battle of Montaperti, in which the outnumbered Sienese Ghibellines inflict a noteworthy defeat to the Florentine Guelphs, will gain notoriety for an act of treachery by a member of the Florentine army, Bocca degli Abati, who at the outset of the battle had hacked off the hand of the Florentine’s standard bearer, sowing immediate confusion in the Guelph ranks and turning the tide of the battle.
Dante Alighieri (himself a Guelph) will immortalize this act in his fourteenth century poem The Divine Comedy.
Almost half the Florentine army (some fifteen thousand men) are killed as a result.
(So crushing is the defeat that even today if the two cities meet in any sporting event, the Sienese supporters are likely to exhort their Florentine counterparts to “Remember Montaperti!”.)