He served as Secretary of the Sacred Congregation for the Discipline of the Sacraments in the Roman Curia from 1965 to 1969, and was elevated to the cardinalate in 1969.
Giacomo Violardo was born in Govone, and studied at the seminary in Alba, the Theological Faculty of Turin (from where he obtained his licentiate in theology), and the Pontifical Roman Athenaeum S. Apollinare in Rome (earning his doctorate in canon and civil law).
Ordained to the priesthood on 29 June 1923, he then furthered his studies at the Catholic University of Milan, from where he received a doctorate in jurisprudence.
From 1928 to 1935, Violardo was professor of moral theology and of canon law at the Pontifical Regional Seminary Pio XI in Fano.
He received his episcopal consecration on the following 19 March from Pope Paul himself, with Archbishops Francesco Carpino and Ettore Cunial serving as co-consecrators, in St. Peter's Basilica.