Adalbert Atto (or Adalberto Azzo) (died 13 February 988) was the first Count of Canossa and founder of that noble house which eventually was to play a determinant role in the political settling of Regnum Italicum and the Investiture Controversy in the eleventh and twelfth centuries.

[1] With Adelaide of Italy, he negotiated a division of power with the bishop of Reggio whereby the bishop was confirmed as comes civitatis, count of the city, and Adalbert as comes comitatus, count of the county, where the county was said to begin three or four miles outside the city walls.

He appears with a similar title, comes comitatus Mantuanensis, in Mantua in a letter of the abbess of Santa Giulia dated 10 June 977.

When Henry II, Duke of Bavaria, was acclaimed as king that year, he united Parma, the County of Piacenza, Bergamo, Cremona, and Brescia to Adalbert's territories.

[citation needed] Adalbert married the Supponid Hildegard (Ildegarda) and had three sons: Geoffrey, Bishop of Brescia, Tedaldo Count of Reggio, as well as Rudolph, who predeceased him.