From Giovanni Villani’s Chronicle – in 1289 after their victory at Campaldino the Florentines move to invest Arezzo proper, whose forces had been lead by their bishop. Medieval banter ensues.
And the said Florentine host being at Arezzo, in the old palace of the bishops, for twenty days, they laid waste all round about them, and they ran their races there on the feast of S. Giovanni, and erected there many engines, and hurled into the city asses with mitres on their heads, in contempt and reproach of their bishop, and raised many wooden towers and other works to attack the city
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