(Canto 6, lines 64-66)
Referring to the Black and White factions clashing with each other on Piazza Santa Trinita in Florence in May 1300, where youth from the Donati and Cerchi families broke out fighting during the Calendimaggio (carnival) celebrations. One of the Cerchis was hurt, which escalated the conflict between the families. In history writing of the time, the event was assigned a pivotal significance in the long standing Black-White conflict.
The "rustic party" are Cerchi's side, the Whites, since they had roots in the country. They had something of a reputation of being "nouveaux riches", possessing proud tempers and rustic habits. "The other" are of course the Blacks, Donati's party. After the May 1300 incident, the ruling officials of Florence (among whom were, at the time, Dante) decided in June to banish the main offenders on both sides from the city. In June the following year, after Black party plans for a coup had been discovered, all the important Black leaders were banished and levied heavy fines.