Arialdus

Milanese deacon

Also known as: Arialdo

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June 18, 2026

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Arialdus was a Milanese deacon who was a significant figure in the Gregorian Reform movement of the 11th century. This reform aimed to improve the moral integrity and independence of the clergy. While often associated with the investiture controversy, the reform's core concerns were canonical elections, the prohibition of simony (the purchase of church offices), and clerical celibacy. Milan, where Arialdus was active, was a powerful city with a history dating back to Gallic settlements, later becoming a major center in the Roman Empire and eventually establishing itself as a commune with autonomous governance.12

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Patarine
…because, under the leadership of Arialdus (Arialdo), a deacon of Milan, its members used to assemble in the Pataria, or ragmen’s quarter of the city (pates being a dialectal word for “rag”). Viewed by the church as heretical, the Patarines, though short-lived in terms of organized activities, became an impetus…
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…because, under the leadership of Arialdus (Arialdo), a deacon of Milan, its members used to assemble in the Pataria, or ragmen’s quarter of the city (pates being a dialectal word for “rag”). Viewed by the church as heretical, the Patarines, though short-lived in terms of organized activities, became an impetus…
Read More