The tyrannical Ezzelino III from Bassano drove the Guelphs out of Vicenza, and caused his brother, Alberico, to be elected podestà in 1230. The independent commune joined the Second Lombard League against Emperor Frederick II who sacked the city in 1237, after which it was annexed to Ezzelino's dominions. On his death the old oligarchic republic political structure was restored – a consiglio maggiore ("grand council") of four hundred members and a consiglio minore ("small council") of forty members – and it formed a league with Padua, Treviso and Verona. Three years later the Vicentines entrusted the protection of the city to Padua, so as to safeguard republican liberty; but this protectorate (custodia) quickly became dominion, and for that reason Vicenza in 1311 submitted to the Scaligeri lords of Verona, who fortified it against the Visconti of Milan.
The tyrannical Ezzelino III from Bassano drove the Guelphs out of Vicenza, and caused his brother, Alberico to be elected podestà in 1230. The independent commune joined the Second Lombard League against Emperor Frederick II who sacked the city in 1237, after which it was annexed to Ezzelino's dominions. On his death the old oligarchic republic political structure was restored – a consiglio maggiore ("grand council") of four hundred members and a consiglio minore ("small council") of forty members – and it formed a league with Padua, Treviso and Verona. Three years later the Vicentines entrusted the protection of the city to Padua, so as to safeguard republican liberty; but this protectorate (custodia) quickly became dominion, and for that reason Vicenza in 1311 submitted to the Scaligeri lords of Verona, who fortified it against the Visconti of Milan.