But in a second and more important campaign, in which the militia of the other Guelf towns of Tuscany took part, the Florentines were signally defeated at Montaperti on the 4th of September 1260.
For some time Siena remained faithful to the Ghibelline cause; nevertheless Guelf and democratic sentiments began to make head.
Exasperated by the tyranny of the Salimbeni and other patrician families allied to the Ghibellines, it decreed in 127 7 the exclusion of all nobles from the supreme magistracy (consisting since 1270 of thirty-six instead of twenty-four members), and insisted that this council should be formed solely of Guelf traders and men of the middle class.
Memmingen, first mentioned in a document of Iwo, belonged originally to the Guelf family, and later to the Hohenstaufens.
They took opposite sides in the great strife of the time between pope and emperor, and were Guelf and Ghibelline by old tradition, or as one or other faction prevailed in them.