Battle of Montaperti

Timeline

1. 1258–1260Tuscany · TuscanyAfter expelling Ghibelline families, Florence became the core of the Guelph camp, while Siena leaned toward the imperial side. After 1258 the two contested control of Tuscan city-states, and Florence organized a league to overwhelm Siena with superior numbers.
2. 1260Siena · TuscanySiena appealed to Manfred, who dispatched German heavy cavalry led by figures such as Jordanus Lancia. Florentine Ghibelline exiles (like Farinata of the Uberti family) also joined the Siena army, shifting the balance away from a mere clash of city militias.
3. 1260Montaperti · TuscanyOn 4 September the two armies fought at Montaperti. The Florentine coalition outnumbered the enemy, but accounts record an insider cutting down the standard-bearer, and the German cavalry charge threw the Guelph ranks into disorder. Florence was badly defeated, with many soldiers dying in the Arbia valley, though later casualty figures are exaggerated and should not be taken as precise statistics.
4. 1260Florence · TuscanyWhen news of the defeat reached Florence, the Guelph leaders fled and the Ghibellines briefly took power; the city's fortifications were at one point dismantled. Siena gained prestige but failed to establish stable Tuscan hegemony; after Manfred fell in battle in 1266, Guelph forces resurged with Angevin support.