Atto of Vercelli or Atto II (885-961) was a Lombard who became bishop of Vercelli in 924. He served as Grand Chancellor to Hugh of Provence and Lothar II, both Kings of Italy in the 10th century. During his time as bishop, Atto was known for his devotion to the welfare of the people in his diocese, both temporal and spiritual, and the vigor with which he attacked ecclesial corruption. He wrote several works in his lifetime. His major compositions include Polypticum, a treatise on the morality of Italy in the day; De pressuris ecclesiasticis, an essay regarding ecclesiastical authority; and the Capitulare, a collection of canon law from his area, including some of the False Decretals, augmented by his own additions of ecclesiastic law. A small selection of his sermons survives in written form. He died in 961.
Atto was born around 885 CE and lived approximately seventy-five years, dying on December 31, 961 CE. He was born into a noble Lombard family; his father was man named Aldegarius. Atto’s writing later in life shows a mastery of Latin and Greek – Latin being the only common language in Italy by the 9th Century – which indicates that his education must have been substantial, in line with the social standing of his family. Little else is known about Atto’s childhood or ecclesiastic career beginnings.
Atto’s rise to become bishop of Vercelli was the consequence of a violent attack on the city of Pavia. The invading army was Hungarian in origin. In 924 CE, forces entered Italy, descending upon Pavia on March 12.Ragembert, Atto’s predecessor as bishop of Vercelli, was in Pavia at the time, and perished in the event. This left the bishopric of Vercelli open for Atto, who must have been a prominent member of the clergy in Vercelli already to be eligible for the position. The episcopate put Atto in contact with many powerful men, including Hugh of Provence, King of Italy; Lothar II, King of Italy and Hugh’s son; and the margrave Berengar II. He served as Grand Chancellor to both Hugh of Provence and Lothar II during their respective reigns over the Kingdom of Italy. His position with Lothar II began in May of 950. Atto did not agree with Lothar’s unjust means of ruling, but was unsuccessful in making any real changes, as he could only council the young king.