Ettore Baranzini was born on 22 September 1881 in Angera, Italy. His studied at the Pontifical Lombard Seminary from 1899 to 1902. He earned degrees in philosophy from the Pontifical Academy of Saint Thomas Aquinas and in theology and canon law at the Pontifical Gregorian University. He was ordained a priest of the Archdiocese of Milan on 27 March 1904 and in December began a fifteen-year stint secretary to Alessandro Lualdi, the new Archbishop of Palermo. On 28 July 1920, he was named Rector of the Pontifical Lombard Seminary, his alma mater, which Pope Benedict XV had just restored as an independent institution. He attended the 1922 conclave that elected Pope Pius XI as an assistant to Lualdi.