Roman Catholic Diocese of Alessandria

The Diocese of Alessandria is a Roman Catholic ecclesiastical territory in Piedmont, northern Italy. It is a suffragan of the diocese of Vercelli.
In 1168, in response to the aggression of Emperor Frederick Barbarossa, the leaders of Milan, Cremona and Piacenza, established a new town in order to discomfit Frederick's ally Pavia. Seeking support for their undertaking, they sent ambassadors to Pope Alexander III in 1170, announcing that they had named the new city in his honor and begging for his support. They offered the city to the Papacy to be forever the vassal of the Holy Roman Church. Alessandria was made a see in 1175 by Pope Alexander III, with territory removed from the diocese of Acqui. The clergy of Acqui objected, of course, and, at a vacancy in the bishopric of Alessandria, they sometimes attempted to elect a bishop of their own; the Papacy was therefore faced with the need to sort out conflicts between the Chapter of Alessandria and the Chapter of Acqui.

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